1 John 2:7

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.
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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.

George Leo Haydock

AD 1849
An old commandment. And again, a new commandment. He means the commandment of charity, or of the love of God and the love of our neighbour. This he calls both an old and a new precept. It may be called old, not only as being a precept of the law of nature, and always obligatory, but because St. John and the other apostles had delivered it to them long ago, i.e. when these persons were first converted. It may also be called a new precept, St. John recommending it anew to them in this epistle, and declaring it to be enjoined in a particular manner by our Saviour Christ, after it had been misconstrued and neglected, especially as it regards our neighbour, that is, every one without exception; so that if any one hate another, it is in vain that he pretends to walk in the light of the gospel. (Witham) A new commandment; viz. the commandment of love, which was given in the old law, but was renewed and extended by Christ. See John xiii. 33. (Challoner)

Knowing this first, that no prophecy of the scripture is of any private interpretation - 2 Peter 1:20

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