Romans 8:12-17 NRSV
So then, brothers and sisters, we are debtors, not to the flesh, to live according to the flesh— for if you live according to the flesh, you will die; but if by the Spirit you put to death the deeds of the body, you will live. For all who are led by the Spirit of God are children of God. For you did not receive a spirit of slavery to fall back into fear, but you have received a spirit of adoption. When we cry, “Abba! Father!” it is that very Spirit bearing witness with our spirit that we are children of God, and if children, then heirs, heirs of God and joint heirs with Christ—if, in fact, we suffer with him so that we may also be glorified with him.
NRSV: New Revised Standard Version