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. 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.
8:15 The Greek word for "adoption to sonship" is a term referring to the full legal standing of an adopted male heir in Roman culture; also in verse 23.
8:15 Aramaic for "father"