6 So we are lying if we say we have fellowship with God but go on living in spiritual darkness; we are not practicing the truth. 7 But if we are living in the light, as God is in the light, then we have fellowship with each other, and the blood of Jesus, his Son, cleanses us from all sin.
8 If we claim we have no sin, we are only fooling ourselves and not living in the truth. 9 But if we confess our sins to him, he is faithful and just to forgive us our sins and to cleanse us from all wickedness. 10 If we claim we have not sinned, we are calling God a liar and showing that his word has no place in our hearts.
My dear children, I am writing this to you so that you will not sin. But if anyone does sin, we have an advocate who pleads our case before the Father. He is Jesus Christ, the one who is truly righteous. 2 He himself is the sacrifice that atones for our sins—and not only our sins but the sins of all the world.
3 And we can be sure that we know him if we obey his commandments. 4 If someone claims, “I know God,” but doesn’t obey God’s commandments, that person is a liar and is not living in the truth. 5 But those who obey God’s word truly show how completely they love him. That is how we know we are living in him. 6 Those who say they live in God should live their lives as Jesus did.
7 Dear friends, I am not writing a new commandment for you; rather it is an old one you have had from the very beginning. This old commandment—to love one another—is the same message you heard before. 8 Yet it is also new. Jesus lived the truth of this commandment, and you also are living it. For the darkness is disappearing, and the true light is already shining.
9 If anyone claims, “I am living in the light,” but hates a fellow believer,* that person is still living in darkness. 10 Anyone who loves a fellow believer* is living in the light and does not cause others to stumble. 11 But anyone who hates a fellow believer is still living and walking in darkness. Such a person does not know the way to go, having been blinded by the darkness.