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.