1 John 3:1-10
See what love the Father has given us, that we should be called children of God; and so we are. The reason why the world does not know us is that it did not know him.
Beloved, we are God's children now; it does not yet appear what we shall be, but we know that when he appears we shall be like him, for we shall see him as he is. And every one who thus hopes in him purifies himself as he is pure. Every one who commits sin is guilty of lawlessness; sin is lawlessness.
You know that he appeared to take away sins, and in him there is no sin. No one who abides in him sins; no one who sins has either seen him or known him. Little children, let no one deceive you. He who does right is righteous, as he is righteous. He who commits sin is of the devil; for the devil has sinned from the beginning. The reason the Son of God appeared was to destroy the works of the devil. No one born of God commits sin; for God's nature abides in him, and he cannot sin because he is born of God.
By this it may be seen who are the children of God, and who are the children of the devil: whoever does not do right is not of God, nor he who does not love his brother.