Romans 8:9-11, 14

But you are not ruled by the power of sin. Instead, the Holy Spirit rules over you. This is true if the Spirit of God lives in you. Anyone who does not have the Spirit of Christ does not belong to Christ. If Christ lives in you, you will live. Though your body will die because of sin, the Spirit gives you life. The Spirit does this because you have been made right with God. The Spirit of the God who raised Jesus from the dead is living in you. So the God who raised Christ from the dead will also give life to your bodies. He will do this because of his Spirit who lives in you.

Those who are led by the Spirit of God are children of God.