Romans 8:14-17 (NIV)
14 because those who are led by the Spirit of God are sons of God.
15 For you did not receive a spirit that makes you a slave again to fear, but you received the Spirit of sonship. And by him we cry, “Abba, Father.”
16 The Spirit himself testifies with our spirit that we are God’s children.
17 Now if we are children, then we are heirs–heirs of God and co-heirs with Christ, if indeed we share in his sufferings in order that we may also share in his glory.