1 John 2:3-11 (New International Version)

 ³We know that we have come to know him if we obey his commands. ⁴The man who says, "I know him," but does not do what he commands is a liar, and the truth is not in him. ⁵But if anyone obeys his word, God's love^[a] is truly made complete in him. This is how we know we are in him: ⁶Whoever claims to live in him must walk as Jesus did.

 ⁷Dear friends, I am not writing you a new command but an old one, which you have had since the beginning. This old command is the message you have heard. ⁸Yet I am writing you a new command; its truth is seen in him and you, because the darkness is passing and the true light is already shining.

 ⁹Anyone who claims to be in the light but hates his brother is still in the darkness. ¹⁰Whoever loves his brother lives in the light, and there is nothing in him^[b] to make him stumble. ¹¹But whoever hates his brother is in the darkness and walks around in the darkness; he does not know where he is going, because the darkness has blinded him.