1 John 2:5-10

But whoso keepeth his word, in him verily is the love of God perfected: hereby know we that we are in him. He that saith he abideth in him ought himself also so to walk, even as he walked.
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. Again, a new commandment I write unto you, which thing is true in him and in you: because the darkness is past, and the true light now shineth.
He that saith he is in the light, and hateth his brother, is in darkness even until now. He that loveth his brother abideth in the light, and there is none occasion of stumbling in him.