We did not receive a spirit of slavery that leads back into fear. We received the Spirit of adoption (Rom 8:15, paraphrased).
By that Spirit we cry “Abba, Father”.
Abba is the Aramaic word Jesus used in Gethsemane (Mark 14:36). Paul uses it again in Gal 4:6. Believers address God with the same word the Son used.
The Spirit also testifies with our spirit that we are God’s children (Rom 8:16).
The adoption has three features
- Immediate. It happens when we come to faith.
- Comprehensive. Full sonship. There is no lesser category of child.
- Irrevocable. It does not lapse.
Paul’s readers would have heard this against Roman law. See Roman adoption.
It makes us heirs
If children, then heirs. Heirs of God and joint heirs with Christ (Rom 8:17).
That comes with a condition. See Suffering precedes glory.