The first six chapters [of the Didache] are evidently adapted for those who need elementary instruction, more particularly for Catechumens of Gentile descent, as distinct from Jewish candidates for Baptism. The remaining chapters of the Didache relate chiefly to the administration of Baptism, to Prayer, Fasting, and to the services of the Lord's Day, and to the celebration of the Agape and the Eucharist. This same division of subjects is observed in the two classes of S. Cyril's Catechetical Lectures. 

   The Didaché was taken as the basis of other manuals of instruction, as is evident from the fact that the greater part of the first six chapters is imbedded in "The Apostolical Church Order," supposed to date from Egypt in the third century. ("The Catechetical Lectures of S. Cyril." Introduction: Catechetical Instruction. Schaff, Philip Ed. 1893. PDF. Nicene and Post-Nicene Fathers. Series 2. Vol. 7. Grand Rapids, MI: Christian Classics Ethereal Library.)

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