Didache {teach}

 (ˈdɪdəˌkiː) 

n

(Theology) a treatise, perhaps of the 1st or early 2nd century ad, on Christian morality and practices. Also called: the Teaching of the Twelve Apostles

[C19: from Greek, literally: a teaching, from didaskein to teach]

Collins English Dictionary – Complete and Unabridged

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