Part 3: Adoption’s Importance and Recovery (read the other parts here)
So how important is the doctrine of adoption and why should it be recovered? Its importance should not be evaluated by considering the number of times the term adoption is actually used in Scripture. One of the other reasons adoption has been neglected in church history, in addition to the one mentioned earlier, may be because Christians failed to recognize its importance since the term is only used five times in Scripture—all found in Paul’s epistles (Romans 8:15, 23; 9:4; Galatians 4:5; and Ephesians 1:5). But we must be careful never to determine the importance of a doctrine solely based on the number of times Scripture uses it. For example, I think we would all agree that the Trinity is a doctrine of fundamental importance to the Christian faith. Yet the word Trinity is nowhere to be found in Scripture. Clearly, the importance of the doctrine of the Trinity is not determined by the frequency of its use as a term in Scripture. Its importance is established in other ways.
If adoption's importance is not established by considering how many times it is used in Scripture, how is it established? Answer: by considering the way Scripture uses the word adoption. If you read the five Pauline texts where the term adoption occurs, you will observe that God’s work of adoption has a “marking” function in the history of redemption. It not only bookends the story of salvation (Ephesians 1:5 and Romans 8:23), as we will see shortly, but it also shows up at climactic junctures within the outworking of redemption in human history (Romans 9:4 and Galatians 4:5). In other words, adoption plays a key role from the beginning of the unfolding story of redemption (before God even created the world) all the way to the end (when all of God’s adopted children enjoy the full privileges of their adoption in the new heaven and new earth). We will begin to explore this in part 4.