Brethren, I write no new commandment unto you, but an old commandment which you had from the beginning. The old commandment is the word which you have heard from the beginning.
All Commentaries on 1 John 2:7 Go To 1 John 2
Augustine of Hippo
AD 430
What commandment calls he old? Which you had, says he, from the beginning. Old then, in this regard, that you have already heard it: otherwise he will contradict the Lord, where He says, A new commandment give I unto you, that you love one another. John 13:34 But why an old commandment? Not as pertaining to the old man. But why? Which you had from the beginning. The old commandment is the word which you have heard. Old then, in this regard, that you have already heard it.