v15 For ye have not received the spirit of bondage again to fear; but ye have received the Spirit of adoption, whereby we cry, Abba, Father.
We have received the Spirit of adoption which is our guarantee that the adoption will take place. Keep reading...
v23 And not only they, but ourselves also, which have the firstfruits of the Spirit, even we ourselves groan within ourselves, waiting for the adoption, to wit, the redemption of our body.
The Spirit has promised that the adoption will have. It's a future event for those who are in Christ. The adoption is the redemption of our body.