See how much the Father has loved us! His love is so great that we are called God's children---and so, in fact, we are. This is why the world does not know us: it has not known God.
My dear friends, we are now God's children, but it is not yet clear what we shall become. But we know that when Christ appears, we shall be like him, because we shall see him as he really is.
Whoever continues to sin belongs to the Devil, because the Devil has sinned from the very beginning. The Son of God appeared for this very reason, to destroy what the Devil had done.
Here is the clear difference between God's children and the Devil's children: those who do not do what is right or do not love others are not God's children.
We must not be like Cain; he belonged to the Evil One and murdered his own brother Abel. Why did Cain murder him? Because the things he himself did were wrong, and the things his brother did were right.
Those who obey God's commands live in union with God and God lives in union with them. And because of the Spirit that God has given us we know that God lives in union with us.