There is something extremely comforting about knowing that God is our father. This relationship has been planned since before the foundation of the world. We have been adopted as sons and daughters into the family of the Triune God through the Son in the Spirit.
Certain statements grab our imagination. For me, J.I. Packer’s assertion about the doctrine of adoption has provoked much thoughtful reflection. He wrote that adoption ‘is the highest privilege the gospel offers: higher even than justification.’It is an amazing truth that when considered for an extended period should humble us and cause rejoicing in the relationship that we now have with the Triune God.
Yet, the striking reality is that while this blessing of our salvation is immense, the language of adoption is unique to Paul and only appears five time in his writings (Rom 8:15, 23; 9:4; Gal 4:5; Eph 1:5). Even while the language of God’s fatherhood and the sonship of particular people (i.e. Adam and David) and the nation of Israel, the concept of adoption never shows up in the Old Testament, and Paul only uses the language when he is writing to a church in a city under direct rule of Roman law. Thus, what we see is that Paul reflects on what God has done in Christ and uses adoption as understood in Roman law as a metaphor for this reality.
Even while the language of adoption is used sparingly in the Bible, the importance of this doctrine is profound. Nevertheless, when we look at many standard treatments of Christian theology (i.e. Turretin, Bavinck, Berkhof, etc.) the doctrine of adoption is underdeveloped and/or subsumed into justification. However, in recent years there have been various studies which are starting to reclaim the doctrine of adoption. I want to argue that we cannot fully appreciate the nature of this doctrine unless we consider it in a Trinitarian perspective. In this I follow Herman Bavinck who stated:
The thinking mind situates the doctrine of the Trinity squarely amid the full-orbed life of nature and humanity. A Christian’s confession is not an island in the ocean but a high mountaintop from which the whole creation can be surveyed. And it is the task of Christian theologians to present clearly the connectedness of God’s revelation with, and its significance for, all of life. The Christian mind remains unsatisfied until all of existence is referred back to the triune God, and until the confession of God’s Trinity functions at the center of our thought and life.
We have been adopted by the Father through the Son, by the Spirit into the family of God as sons and daughters, not by nature but by grace. It seems that examining the doctrine of adoption in its Trinitarian contours will only aid us in our grasping “how wide and long and high and deep is the love of Christ” (Eph 3:18).