The Letter to Diognetus is longer than my typical web page. Do not miss chapters 5 and 9! There is very little like them in all of Christian history (though John Calvin's letter to Cardinal Sadolet is pretty impressive, too).
This rendition of the Letter to Diognetus is in my own words, taken from the Ante-Nicene Fathers, vol. I. I haven't left anything out, and where any important issue comes up, I've leaned towards not changing the wording of the Edinburgh translators.
Their work, however, is over a century old, so you'll find this version much easier to read.
As you read, you'll find my comments sprinkled throughout in text boxes. These are not meant to interpret the text for you, although I do some of that. Instead, I'm trying to show you what early Christianity was like. It is very hard to find a better introduction to late 1st century Christianity than the Letter to Diognetus.
Why is it so good? You'll notice that the writer does not quote a single Scripture, neither from the Old Testament nor the New. He is the only early Christian writer not to do so.
Nonetheless, you'll also recognize his thoughts as Scriptural. This is a man who is telling you what he was taught in a church established by apostles (ch. 11), not a man who is interpreting the Bible for himself.
This is an awesome thing, as it makes the Letter to Diognetus a much better insight into early Christianity than it otherwise would have been.
I see, most excellent Diognetus, the exceptional desire you have to learn the method of worshipping God that prevails among the Christians. You inquire about them with great care and sincerity, seeking to determine what God they trust in and what type of religion they observe that allows them to look down upon the world and to despise death, all the while rejecting both those that are esteemed gods by the Greeks and the superstitions of the Jews.
I hear you asking how they have the kind of affection that is cherished among them and why this new type or practice of religion has only now and so recently come into the world.
I welcome this desire of yours, and I implore God, who enable us both to speak and to hear, to let me speak in such a way that, more than anything, I may hear that you have been built up. And I ask him to enable you to hear in such a way that I, the one speaking, may have no reason to regret doing so.
The early Christians were not afraid to take on the foolishness of idol worship, as the Letter to Diognetus does here.
I have to admit I find these attacks on idolatry interesting as well as powerful.
Isn't one a stone like the ones we walk on? isn't a second brass, no better than containers which are made for everyday use? Isn't a third wood and already rotting at that? Isn't a fourth silver, which needs a man to watch it so that it's not stolen? Isn't a fifth iron, consumed by rust? Isn't a sixth clay, no more valuable than what's made for the humblest uses?
Aren't all of these corruptible matter? Aren't they all made with fire and with iron tools? Didn't the sculptor fashion one of them, the brazier a second, the silversmith a third, and the potter a fourth? Wasn't every one of them, in its own way, subject to change before they were formed by the skills of these workmen into the shape they're in?
Wouldn't those things which are now containers, formed from the same materials, become just like the gods if they had run into the artisans who made your gods? Couldn't these, which are now worshipped by you, be made by men into containers similar to the others?
Are they not all deaf? Are they not all blind? Are they not without life? Are they not destitute of feeling? Are they not incapable of motion? Are they not all liable to rot? Are they not all perishable?
You call these things gods! You serve them! You worship them! And you become exactly like them.
It's for this reason you hate the Christians, because they do not consider these to be gods. But don't you, who think and suppose these articles to be gods, treat them with much greater contempt than the Christians? Don't you mock and insult them ever more when you worship things that are made of stone and clay without appointing anyone to guard them, but the ones made of silver and gold you lock up at night and appoint guards for them during the day so that they won't be stolen?
And when you attempt to present gifts to them, then if they are possessed of sense, don't you punish rather than honor them? On the other hand, if they have no sense, you prove it by worshipping them with blood and the smoke of sacrifices. Would any of you stand for such indignities? Let any one of you tolerate having that done to yourself!
Not a single human being will put up with that kind of treatment unless he's forced to, and it's because he's endowed with sense and reason. A stone, however, readily endures it because it has no feeling.
You certainly don't indicate that they are possessed of feeling. So in regard to the fact that Christians are not used to serving gods like that, I could easily find many other things to say; however, if what has already been said is not enough for anyone, then I consider it a waste of time to say anything else.
Is the Letter to Diognetus really calling the sacrifices of the Jews, commanded by Moses in the Law, foolishness?
He is, and here's why.
Christians of the second century presented the most amazing Scriptural arguments, based on Jer. 7:22-23 and Ps. 51:16-17, that God was not interested in sacrifices from Israel. They argued that God only gave them sacrifices after their fathers sinned with the golden calf.
The sacrifices, then, were not for God; they were for the Jews, who did not all have the Spirit as New Testament disciples do. The fleshly Jews needed things like sacrifices to keep their attention directed to God—though even this didn't work—but God never wanted them.
Read those two Scriptures I just gave you, and then read Exodus from chapter 20 (the delivery of the 10 commandments) forward, and see if you don't agree with the argument of the early Christians, which is not only here in the Letter to Diognetus, but is consistent and repeated throughout the 2nd century writings.
Next, I'd guess that you most want to hear something about why the Christians don't observe the same forms of divine worship as the Jews.
So then, if the Jews abstain from the kind of service described above [i.e., blood sacrifices and burnt offerings] and count it proper to worship one God as the Lord of all, [then we can agree with them]. However, if they offer him worship in the way we've described, they are in great error.
The Gentiles, when they offer [sacrifices] to things that are destitute of feeling and hearing, provide an example of madness. The Jews, on the other hand, when they think to offer these things to God as if he needed them, ought to consider their sacrifices an act of foolishness rather than divine worship. For the One that made heaven and earth and everything in them, and who gives us everything we need, certainly does not require any of those things which he himself bestows on the very ones who are thinking to provide them to him!
Those who imagine that they are offering sacrifices to him with blood and the smoke of sacrifices and burnt offerings, and who think that by such "honors" they are showing him respect—well, these people who suppose that they can give anything to the One who stands in need of nothing appear to me to be no different than those who studiously confer the same honor on things that are destitute of feeling and therefore incapable of enjoying such honors.
This note is to complement the sidebar above, so make sure you read that first.
Apparently, this author was unfamiliar with the Scriptures, so he doesn't address them. However, the argument that God is not in need of sacrifices is commonly given as an argument against the Jews in other 2nd century writings.
Here, as throughout this letter, we find that the anonymous author of the Letter to Diognetus is thoroughly and accurately taught and deeply immersed in early Christian doctrine, even though he is unfamiliar with the Scriptures themselves.
Again, the writer of the Letter to Diognetus is not familiar with the Scriptures. He is, however, familiar with Christian arguments made by those who are familiar with the Scriptures.
Other early Christians did indeed argue that it is foolish to reject some creatures of God and accept others. That may seem to be unscriptural, but Jesus says basically the same thing in Mark 7:18-19. He marvels that they can't figure out that food can't defile a person.
The early Christians said that the Scriptures on food had a symbolic meaning. The man that is clean is the one who ruminates on the word of God (chews the cud), and who separates from the world (parts the hoof).
In the same way, the Letter of Barnabas argues that a day can only be sanctified by our living pure lives, which we must do every day. Thus, Justin Martyr says that "the new law requires that we keep perpetual Sabbath" (Dialogue with Trypho 12).
So although the Letter to Diognetus doesn't appeal to Scriptural arguments, it is clear that the author has heard the same arguments that are detailed more scripturally in later 2nd century writings.
As far as their meticulous attention to food, their superstition in regard to the Sabbaths, their boasting about circumcision, and their whims about fasting and the new moons—which are utterly ridiculous and unworthy of attention—I don't think you need to learn anything from me. How can it be lawful to accept some of those things which have been formed by God for human use as properly made and to reject others as useless and unnecessary?
And to speak falsely of God, as if he forbids us to do what is good on the Sabbath days, in what way is this not ungodly? To glory in the circumcision of the flesh as a proof of election—as though because of it they are especially loved by God—how can this not be a subject of ridicule?
And as for observing months and day, who would deem it a part of divine worship to wait for the stars and moon to make appointments for God according to whatever tendencies they have? Isn't it much rather a demonstration of foolishness to let the changing of the seasons determine whether you are festive or mourning?
I'm going to suppose, then, that this is sufficient to convince you that Christians are correct in abstaining from the pride and error that is so common and from the nosiness and useless boasting of the Jews.
But you must not hope to learn the mystery of their unique way of worshipping God from any mortal.
Take special note of this chapter!
Chapter five of the Letter to Diognetus is one of the most poetic and beautiful passages in all of Christian history.
Even more importantly, this is not wishful thinking. This is the way Christians were living in the late first and early 2nd centuries. This is how they were known.
It's no wonder, then, that a century later, Tertullian would describe the Romans as marveling at the Christians with statements like "Behold how the love one another" and "How they are even ready to lay down their lives for one another!" (Apology 39). Christians of the 2nd century set a very high standard.
Among us you will find uneducated persons, craftsmen, and old women, who, if they are unable in words to prove the benefit of our doctrine, yet by their deeds exhibit the benefit arising from their persuasion of its truth. They do not rehearse speeches, but exhibit good works; when struck, they do not strike again; when robbed, they do not go to law; they give to those that ask of them, and love their neighbors as themselves. (Athenagoras, A Plea for the Christians 11, A.D. 177)
Christians are not distinguished from other men by country, language, nor by the customs which they observe. They do not inhabit cities of their own, use a particular way of speaking, nor lead a life marked out by any curiosity. The course of conduct they follow has not been devised by the speculation and deliberation of inquisitive men. The do not, like some, proclaim themselves the advocates of merely human doctrines.
Instead, they inhabit both Greek and barbarian cities, however things have fallen to each of them. And it is while following the customs of the natives in clothing, food, and the rest of ordinary life that they display to us their wonderful and admittedly striking way of life.
They live in their own countries, but they do so as those who are just passing through. As citizens they participate in everything with others, yet they endure everything as if they were foreigners. Every foreign land is like their homeland to them, and every land of their birth is like a land of strangers.
They marry, like everyone else, and they have children, but they do not destroy their offspring.
They share a common table, but not a common bed.
They exist in the flesh, but they do not live by the flesh. They pass their days on earth, but they are citizens of heaven. They obey the prescribed laws, all the while surpassing the laws by their lives.
They love all men and are persecuted by all. They are unknown and condemned. They are put to death and restored to life.
They are poor, yet make many rich. They lack everything, yet they overflow in everything.
They are dishonored, and yet in their very dishonor they are glorified; they are spoken ill of and yet are justified; they are reviled but bless; they are insulted and repay the insult with honor; they do good, yet are punished as evildoers; when punished, they rejoice as if raised from the dead. They are assailed by the Jews as barbarians; they are persecuted by the Greeks; yet those who hate them are unable to give any reason for their hatred.
The poetry of the Letter to Diognetus continues!
To sum it all up in one word, what the soul is in the body, that is what Christians are in the world.
The soul is dispersed through all the parts of the body, and Christians are scattered through all the cities of the world. The soul lives in the body, yet is not of the body; Christians live in the world, yet are not of the world.
The invisible soul is guarded by the visible body. So Christians are known to be in the world, but their godliness remains invisible.
The flesh hates the soul and wars against it, even though it is not harmed, because it is prevented from enjoying pleasures. In the same way, the world hates the Christians, though not wounded in any way, because they renounce pleasures. The soul loves the flesh that hates it, as well as its parts. Christians, in the same way, love those that hate them.
The soul is imprisoned in the body, yet preserves that very body. Christians are confined in the world as in a prison, and yet they are the preservers of the world. The immortal soul dwells in a mortal tabernacle, and Christians live as travelers in perishable bodies, looking for an imperishable home in the heavens.
The soul becomes better when it is poorly provided with food and drink. Similarly, the Christians, although subjected to punishment on a daily basis, keep increasing in number.
The chapter division in The Ante-Nicene Fathers was really poor. I made the last sentence of their chapter six the first sentence of my Letter to Diognetus chapter seven.
God has assigned them this illustrious position, and it is unlawful for them to forsake it because—as I said—this was no mere earthly fabrication which was delivered to them. Nor is it a merely human system of opinion that they judge it right to preserve so carefully. It is not an endowment of merely human mysteries that has been commetted to them, but truly God himself, who is omnipotent, the Creator of everything, and invisible, has sent the Truth from heaven—the holy and unfathomable Word—placed him among men and firmly established him in their hearts.
He did not, as one might have imagined, send men any servant, angel, ruler, or any of those who influence earthly things, or one of those to whom the government of heavenly things has been entrusted. Instead, he sent the very Creator and Fashioner of all things, the One by whom he made the heavens, by whom he enclosed the seas within its set boundaries, whose ordinances the stars faithfully observe, by whom the sun is told the distance of his daily course to run, whom the moon obeys, being commanded to shine in the night, and whom the stars also obey, following the moon on her route.
Modern gnostics like to argue that Jesus' divinity was an invention of the Council of Nicea. Here, though, in the Letter to Diognetus, perhaps the earliest Christian writing outside the New Testament, Jesus' status as pre-existent Creator is stated clearly and repeatedly.
He has arranged everything, placing everything within its proper limits. Everything is subject to him—the heavens and the things in it; the earth and the things in it; the sea and the things in it; fire, air, and the abyss; things in the heights, in the depths, and which lie in between.
This is the One he sent to them!
Was it, then, as one might guess, for the purpose of tyranny or of inspiring fear and terror?
Never! It was mercy and meekness.
As a king sends his son, who is also a king, so he sent him. As God he sent him. To men he sent him. As a Savior he sent him, and as an attempt to persuade and not compel us.
For violence has no place in the character of God.
As calling us he sent him, not as One pursuing us in vengeance. As loving us he sent him, not as judging us. In the future he will send him to judge us, and who shall endure his arrival?
There's a gap of unknown length in the manuscript of the Letter to Diognetus here
Don't you see them exposed to wild beasts for the purpose of persuading them to deny the Lord, yet they are not overcome? Don't you see that the more of them that are punished, the greater the number of the rest becomes?
This does not seem to be the work of man. This is the power of God. These are the evidences of his appearance.
Among men, was there anyone at all who understood what God is before this Messenger came?
Do you accept the useless and silly doctrines of those who are considered trustworthy philosophers? Some of them said that fire was God. Thus, they were calling something God that they would eventually arrive at themselves. Others said water, and others some other element made by God. But if any of these theories were worthy of approval, then anything else that's been created could be called God.
The philosophers were both the religious and academic leaders of Greek society. Only a few are well known—men like Plato, Aristotle, and Socrates as well as Pythagoras and Euclid of geometry fame. There were many, however, and most of those simply studied whatever they could get their hands on and developed their own philosophical systems and academic ideas.
While the philosophers were the religious leaders of Greek and Roman paganism, the poets were their scriptures. Christians often argued with the Greeks from their own poets. They especially liked Plato, both a philosopher and poet, whose verses they often used to prove there was one God the Creator.
Such declarations are simply the startling and erroneus utterances of deceivers.
No man has seen him or made him known, but he has revealed himself. He has shown himself through faith, which is the only thing to which it has been granted to behold God.
For God, the Lord and Fashioner of all things, who made all things, and who assigned them their various positions, has proven himself not only a Friend of mankind, but also patient. Yes, he always had that type of character, still does, and always will—kind and good, free from anger, true, and the only one who is good.
He formed in his mind a great and unspeakable idea, which he communicated to his Son alone. As long as he held and preserved his wise counsel in concealment, he seemed to neglect us and have no care for us. Afterwards, though, when he revealed and laid open, through his beloved Son, the things which have been prepared from the beginning, he conferred every blessing on us at once!
As a result, we partake of his benefits, we see, and we are active. Which of us could have ever expected these things?
So, he was aware of all things in his own mind, along with his Son, according to the relation that subsisted between them.
It's hard to beat chapter 9 of the Letter to Diognetus for depth and beauty. What an incredible, awe-inspiring description of the atoning work of Christ.
This chapter was life-changing for me. After struggling for years trying to wrap my brain around the general conflict between faith and works in the Bible, and even more so the specific seeming contradiction between Rom. 3:28 and Jam. 2:24, this chapter set me free and gave me a clear understanding. (You can read it here.)
I couldn't buy modern explanations of James 2:24 because they left all of us sola fide Christians in a position where we would never quote that verse in any situation or for any use. We could read it, and we could explain it away, but we could never say it.
The Letter to Diognetus changed all that with one statement: "Once it became obvious that in ourselves we were unable to enter the kingdom of God, the power of God could then make us able." Again, the explanation for that is here.
But the Letter to Diognetus did not only resolve the issue. It did it with poetry and with one of the most extraordinary expressions of gratefulness and praise in all the Christian writings. In my opinion, only Justin's Discourse to the Greeks can rival the beaty and power of this chapter.
As long, then, as that previous era lasted, he allowed us to be carried along by unruly desires and to be dragged around by the longing for pleasure and by various lusts. This wasn't because he delighted in our sins in any way, but he simply endured them. He didn't approve of the time of working iniquity which existed then, but he tried to form a mind conscious of righteousness.
The purpose was that once we were convinced that we are unworthy to attain life through our own works, it would now, by the kindness of God, be bestowed on us. Once it became obvious that in ourselves we were unable to enter the kingdom of God, the power of God could then make us able.
When our wickedness had reached its height, when it had been clearly shown that the its reward, punishment and death, was hanging over our heads, and when the time had come which had appointed for manifesting his own kindness and power, then the one love God, out of exceptional care for mankind, did not regard us with hatred, nor thrust us away, nor remember our iniquity against us. He showed great patience and bore with us.
Then he took the burden of our iniquities on himself. He gave his own Son as a ransom for us—the Holy One for transgressors; the Blameless One for the wicked; the Righteous One for the unrighteous; the Unfading One for the Fading; the Immortal One for those that are mortal.
For what other thing was capable of covering our sins than his righteousness? By whom else was it possible that we, the wicked and ungodly, could be justified, other than by the only Son of God?
O sweet exchange! O inconceivable accomplishment! O benefits beyond any expectation! That the wickedness of many should be hidden in a single Righteous One, and that the righteousness of One would justify many transgressors!
So, he convinced us in the previous era that our nature was unable to attain to life, and he has now revealed the Savior who is able to save even those that it was impossible to save. By both these facts he wanted to lead us to trust in his kindness, and to consider him our Nourisher, Father, Teacher, Counselor, Healer; our Wisdom, Light, Honor, Glory, Power, and Life so that we should not worry about clothing and food.
If you want this faith, the first thing you must receive is the knowledge of the Father.
This presentation of the Gospel in the Letter to Diognetus is unusual—for us.
It's not for the early Christians because they understood the power of the Word of God implanted in human hearts (Jam. 1:18,21). They knew that you could purify your soul by obeying the Truth (1 Pet. 1:22-23) and that Jesus is the author of eternal salvation to all that obey him (Heb. 5:9).
Thus, the Letter to Diognetus can tell us that we should begin by imitating him. He has already made it clear in that glorious 9th chapter that we cannot do this in ourselves. Only the power of God can make us able, he says. The Word of God, Jesus Christ, is our Power and Life, as well as so much more to us.
But once we are aware of where our power comes from, then stepping out in faith by choosing to obey the Word is life-changing. Peter threw his net on the other side of the boat at the word of the Lord (Luk. 5:5) and without another word from the Lord Peter knew he was a sinner (v. 8) and immediately responded to the call to leave everything and follow Christ (vv. 10-11).
Basically the same thing was true of Zaccheus, who simply obeyed Christ's command to come down out of a tree (Luk. 19:5-10).
Thus, the early Christians, knowing the power of the Word of God planted in a heart like a seed through obedience, were not afraid to call their hearers to repent and follow him, even if the words were "imitate his kindness" (as here) rather than "repent and turn to God" (Acts 26:20).
God has loved mankind, and he made the world because of us. He caused everything in it to be subject to us. He gave us reason and understanding. On us alone he bestowed the privilege of looking up to him [This is a reference to upright walking]. He formed us in his own image. He sent his only-begotten Son to us. He promised us a kingdom in heaven, and he will give it to those who have loved him.
When you have attained this knowledge, can you imagine what kind of joy you will be filled with? Think how much you will love this One who has first loved you so much!
If you love him, then you will imitate his kindness.
Do not be surprised that a man can imitate God. He can, if he is willing.
You see, happiness is not found by ruling over neighbors or by trying to hold onto a superiority over those that are weaker. It's not found by being rich, nor by intimidating inferiors. No one can become an imitator of God through these things.
None of those things constitute his majesty.
On the contrary, the imitator of God is the one who takes his neighbor's burden on himself. It's the one who, in whatever way he really is superior, is prepared to help anyone who might be deficient. It's the one who takes what he has received from God, distributes it to the needy, and thus becomes a god to those who receive from him.
In this way you will see, while you are still on earth, that God in the heavens rules. Then you will begin to speak the mysteries of God. Then you will love and admire those that suffer punishment because they will not deny God. You will condemn the deceit and error of the world when you know what it is like to truly live in heaven; when you despise that which is considered death here on earth; when you fear what is really death—that which is reserved for those who will be condemned to the eternal fire and afflict those that are committed to it all the way to the end.
Then you will admire those who endure for righteousness sake the fire that is only for a moment. You will consider them happy when you know that fire.
I am not talking about things that are unfamiliar to me. I do not aim at anything except what is consistent with sound reason.
I have been a disciple of the apostles, and now I am a teacher of the Gentiles. I minister the things that were given to me by men who are disciples worthy of the truth.
This passage of The Letter to Diognetus is an example of the early Christians using the term "the Word" to refer to Christ.
Today, if a person refers to "The Word" without any explanation, we understand him to mean the Bible. Not so in the early churches. When they said "The Word," they were referring to Christ himself.
You will find this is true in Scripture as well, where the early church usage holds up much better. For example, Hebrews 4:12 is constantly understood to refer to the Scriptures by modern Christians, but if verses 12 and 13 are read together, it is obvious that the passage refers to Christ, not the Scriptures.
This is such a problem that the King James Version—along with several modern translations— translate the Greek word spoudazo with "study" in 2 Tim. 2:15, even though it never means study. However, the translators assume that "Word" in that verse is a reference to Scriptures.
That would not typical Scriptural usage. More likely, Paul is referring to God's Word in any form, especially in the form of being the living Word in our hearts (Jam. 1:21; 1 Pet. 1:23-25).
For who that is rightly taught and begotten by the loving Word would not seek to learn accurately the things which have been clearly shown by the Word to his disiples?
The Word appeared and revealed these things to them. He spoke plainly to them. True, he was not understood by the unbelieving, but he spoke with the disciples, the ones who were regarded as faithful by him. In this way they acquired a knowledge of the mysteries of the Father.
This is why he sent the Word, so that he might be shown to the world. He was despised by the people [i.e., the Jews], but when he was preached by the apostles, the Gentiles believed in him.
This is the One who was from the beginning, who appeared as if new, was found old, and who is always being born anew in the hearts of his saints. This is the One who, existing from eternity past, is today honored as the Son. He is the One through whom the Church is enriched and grace, widely spread, increases in the saints. He furnishes understanding, reveals mysteries, announces times, rejoices over the faithful, and gives to those that seek. By him the limits of the faith are not broken through, nor the boundaries set by the fathers passed over.
When this happens the fear of the law is chanted; the grace of the prophets is known; the faith of the Gospels is established; the tradition of the apostles is preserved; and the grace of the Church exults.
The Word is seen in the Letter to Diognetus as guiding those who teach. The "will of the Word" moves the writer to speak.
This is a Scriptural thought. The Book of Acts says repeatedly that the Word of God was preached (e.g., 11:19). It also says that the Word grew and multiplied (6:7; 12:24; 19:20).
How does the Word of God grow and multiply? It grew and multiplied as the disciples multiplied because the Word they preached was the Word of God implanted in their hearts, the word James speaks of (Jam. 1:21).
If you do not grieve this grace, you will know the things the Word teaches. He teaches through whom he wants and whenever he pleases. Whatever things we are moved to speak by the will of the Word that commands us, that we painstakingly communicate to you out of a love of the things which have been revealed to us.
When you've read these things and listened carefully to them, then you will know what bestows on those who love him correctly. They are made a paradise of delight. They produce a tree out of themselves that bears all sorts of produces, flourishes well, and is adorned with various fruits.
In this place the tree of knowledge and the tree of life have been planted. But it is not the tree of knowledge that destroys; it is disobedience that proves destructive.
I'm not sure I completely agree with the Letter to Diognetus' assessment of the tree of knowledge in the garden, but arguing with him is not what I'm here to do. My job is to give you a historical setting for his letter. I think I can do that.
Addressing the issue of knowledge and its role in the Christian life was a common subject among 2nd century writers. Philosophy thrived in Greece and Rome at that time, and knowledge was everything. Luke comments on this in Acts, saying:
For all the Athenians and the tourists there spent their time doing nothing but telling or hearing some new thing. (17:21)
Christians did not want to be like the philosophers who "speak against vices that they themselves live in" [Minucius Felix]. But they also did not want to be devoid of knowledge. Their familiarity with the philosophers and poets of Greece and their knowledge of nature were of great benefit in defending the faith they believed in.
In fact, if you're reading this site and are edified in any way by it, then you are benefitting from knowledge they worked to gain over 18 centuries ago.
Knowledge is spoken both well and poorly of in Scripture, depending on whether it was human or divine wisdom. This explanation by the letter to Diognetus is similar to that which is given by other early apologists.
Truly, the words which are written are not without significance. God planted the tree of life in the midst of paradise and through knowledge revealed the way to life. When those who were the first ones formed did not use it properly, they were stripped naked through the fraud of the snake.
For life cannot exist without knowledge, nor is knowledge secure without life. That is why both were planted close together.
The apostle understood the significance of this, and he criticizes the knowledge which we let influence our lives without true doctrine. He declares, "Knowledge puffs up, but love builds up" [1 Cor. 8:1].
For the one who thinks he knows anything without true knowledge—the kind that is witnessed to by life—knows nothing, but is deceived by the snake because he did not love life. But the one who combines knowledge with fear and searches for life—that one plants in hope, expecting fruit.
Let your heart be wisdom, and let your life be true knowledge, received inwardly.
If you possess this tree and exhibit its fruit, then you will always reap those things which God desires, which the snake cannot reach, and to which deception does not come near. Then Eve will not be corrupted but trusted as a virgin. Salvation will be manifested; the apostles will be [seen as] filled with understanding; and the Passover of the Lord will advance. The choirs will be gathered together, arranged in proper order, and the Word will rejoice in teaching the saints.
By him is the Father glorified; to him be glory forever. Amen.
Well, there you have it. The Letter to Diognetus is one of the most interesting and most important works of Christian antiquity.
It's edifying, too!
I recommend going to our page on early Christianity, when the faith was still warm and vibrant from the fire of the apostles. There you can learn the life and doctrine of the apostles churches, be inspired by them to a more powerful faith, and find out why we so desperately need their influence today.