4 Suppose someone says, "I know him." But suppose that person does not do what God commands. Then that person is a liar and is not telling the truth.
5 But if anyone obeys God's word, then God's love is truly made complete in that person. Here is how we know we belong to him.
6 Those who claim to belong to him must live just as Jesus did.
7 Dear friends, I'm not writing you a new command. Instead, I'm writing one you have heard before. You have had it since the beginning.
8 But I am writing what amounts to a new command. Its truth was shown in how Jesus lived. It is also shown in how you live. The darkness is passing away. The true light is already shining.
9 Suppose someone claims to be in the light but hates his brother or sister. Then he is still in the darkness.
10 Those who love their brothers and sisters are living in the light. There is nothing in them to make them fall into sin.