15 The Spirit you received does not make you slaves, so that you live in fear again; rather, the Spirit you received brought about your adoption to sonship.[a] And by him we cry, “Abba,[b] 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.