The Mystery of Lawlessness
Dear Brother in Yeshua (Jesus Jewish name),
Regardless to how anyone kept the commandments in 1st or 2nd century, the truth is the truth.The sabbath was given as a "covenant" sign a term unfortunately many Universalist-New Age Christians have no regard for. If you are in a covenant relationship you must keep the terms of the covenant = the 10 commandments (not the 10 suggestions), can't change them to suit our fancy.
Sabbath keeping was very much a part of 1st century Christians lives:
Wherefore my judgment is, that we trouble not them that from among the Gentiles turn to God; 20 but that we write unto them, that they abstain from the pollutions of idols, and from fornication, and from what is strangled, and from blood. 21 For Moses from generations of old hath in every city them that preach him, being read in the synagogues every sabbath.
Acts 15:19-21 (ASV)
Now when they had passed through Amphipolis and Apollonia, they came to Thessalonica, where was a synagogue of the Jews: 2 and Paul, as his custom was, went in unto them, and for three sabbath days reasoned with them from the Scriptures,
Acts 17:1-2 (ASV)
There's plenty more evidence of the manners and customs of 1st century believers, right in our blessed scriptures. Remember this one thing, the problem is the last days is not legalism but LAWLESSNESS = anomia = No Law! free to do whatever you want ideology. That's why we have gay preachers, gay Christians, Racist Christians etc....
Lastly, a person can twist the scriptures, but Kepha (Peter) issues a warning to the twisters:
Therefore, beloved, since you are waiting for these, be diligent to be found by him without spot or blemish, and at peace. 15 And count the patience of our Lord as salvation, just as our beloved brother Paul also wrote to you according to the wisdom given him, 16 as he does in all his letters when he speaks in them of these matters. There are some things in them that are hard to understand, which the ignorant and unstable twist to their own destruction, as they do the other Scriptures.
2 Peter 3:14-16 (ESV)
P.S. Keep the Sabbath