1 John 2:8 (KJV)

And hereby we do know that we know him, if we keep his commandments.

He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.

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.

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.

But he that hateth his brother is in darkness, and walketh in darkness, and knoweth not whither he goeth, because that darkness hath blinded his eyes.

I write unto you, little children, because your sins are forgiven you for his name's sake.

I write unto you, fathers, because ye have known him that is from the beginning. I write unto you, young men, because ye have overcome the wicked one. I write unto you, little children, because ye have known the Father.