1 John 2:7
Brethren, I write no new commandment unto you, but an old commandment which ye had from the beginning. The old commandment is the word which ye have heard from the beginning.
1 John 2:19
They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us.