1 John 2:3-6

3 And by this we know that we have known him, if we keep his commandments.

4 He who saith that he knoweth him and keepeth not his commandments is a liar: and the truth is not in him.

5 But he that keepeth his word, in him in very deed the charity of God is perfected. And by this we know that we are in him.

6 He that saith he abideth in him ought himself also to walk even as he walked.