The theological doctrine of adoption is not one that readily comes to most people’s minds. It has often received short shrift in text books of systematic theology and in the church’s confessions, so it is little wonder that even people who can tell you clearly what they believe about justification and sanctification will often give you a blank look when you inquire about adoption. Yet properly understood, adoption is one of the most precious, heartwarming, and practical of all of our theological beliefs. It invites us to consider the amazing privilege that is ours that we should be called the children of God (1 John 3:1). Whereas justification rests primarily on a legal image and invites us to revel in the freedom that comes from our undeserved acquittal at the court of God’s judgment, adoption focuses our attention on a relational image and points us to the joy and assurance that comes from receiving a father who loves us and a family with whom we can enjoy our new freedom in Christ.
Perhaps one reason that we fail to appreciate the privilege of being adopted as God’s children is because we have never considered ourselves to be orphans. We tend to think that by nature everybody is a child of God. After all, didn’t Paul tell the Athenian philosophers that we are all God’s offspring (Acts 17:29)? It is certainly true that there is a sense in which we all have a relationship to God by virtue of our creation in His image. This relationship gives each one of us an innate knowledge of God’s existence and of our duty to worship Him, which is the point Paul was making on Mars Hill. Yet the Scriptures make it clear that there is another sense in which we are not all by nature children of God: on the contrary, there are two families of people on this earth, the children of God and the children of the Devil, who are locked in a perpetual life and death conflict (John 8:44; 1 John 3:10).
The biblical doctrine of adoption begins with Adam and Eve. Being created in the image of God, they were indeed God’s children, enjoying close fellowship with their heavenly Father daily in the garden of Eden. Yet with their fall, the image of God in them was marred and their relationship as children of God was lost. They became outcasts from the garden, alienated from the presence of God, children of His wrath. This is the condition into which all human beings are now born: aliens and strangers with respect to God (Eph. 2:3).
Yet God was not content to leave us in this lost and desolate condition. Because He had chosen before the foundation of the world to have a family for Himself (Eph. 1:5), He acted in time and history to make their salvation a reality. Whereas Adam was God’s son by virtue of creation, Israel became God’s son through adoption (Ex. 4:22). This metaphor for the relationship between God and His people highlights clearly the element of grace in their relationship. There was nothing in Israel by nature that would have drawn God to her (Deut. 7:7). In fact, on the contrary, the prophet Ezekiel pictures Israel at this point in her history as a helpless baby, covered in blood and abandoned by her natural parents, yet chosen by God and brought into His family (Ezek. 16:6). Nor did she earn God’s favor through her subsequent behavior, for the history of her relationship with Him was one of continual unfaithfulness and prostitution (Ezek. 16:15–52). Yet though she constantly spurned and abandoned Him, God still would not abandon her; her election as His adopted child was irrevocable (Rom. 11:29).
In addition to Israel’s adoption as God’s son, the Old Testament also speaks of the adoption of the Davidic king as God’s son (Ps. 2:7). This unique privileged relationship meant that he and his descendants could not be utterly cast off by God in the way that Saul had been cast off because of his failure. Rather, when they sinned, they would be chastised by God as a father chastises his son (2 Sam. 7:14–16). The covenant between God and the line of David was unbreakable, no matter what the offense (Jer. 33:20–21).
These twin themes of the adoption of Israel and the line of David find a common fulfillment in Jesus Christ. In His divine nature, Christ is God’s Son from all eternity, yet as the true Israel and the true son of David, He is the heir of all of the promises of sonship made to Israel and to David. As a result, when we are united to Christ by faith, we too receive a share in that sonship and the privileges that go along with it. As John puts it: “To all who did receive him, who believed in his name, he gave the right to become children of God” (John 1:12). Our adoption as sons of God thus comes through union with Christ and cannot be experienced apart from it. In Christ, and in Him alone, we receive the adoption that gives us an undeserved share in the promises that were made to Him and the privileges that He has earned as God’s Son (Gal. 3:29). Indeed, the reason that Christ came to this earth was so that He might give us adoption as God’s sons (Gal. 4:5).
What, though, are the blessings that flow to us as God’s adopted children in Christ? The first blessing that we have is fellowship with our heavenly Father, a fellowship that our first parents forfeited through their sin. In the Old Testament, God’s people did not normally address Him in prayer as “Father.” Only the Davidic king could appeal to God under that title (Ps. 89:26), on the basis of the covenant God made with David in 2 Samuel 7. No one else could use such an intimate form of address. However, in Christ, the right to come to God as Father is now extended to all those who come to Him by faith, whether Jew or Gentile, male or female, slave or free. Because we are in Christ, we may now come to God, praying “Our Father,” just as Jesus taught us to pray. In Christ, we may be confident that we will never again be left as orphans (John 14:18).
What is more, because believers share a common Father in God, we have the basis for true spiritual unity with one another (Eph. 4:6). If as Christians we all have one Father, then it follows that we are all brothers and sisters. This is why Paul could address Christians in Rome as “brothers,” even though he had never met them (for example, Rom. 8:12). As fellow adopted children, we are all part of the one family of God. This truth is the experience of Christians who travel and live in different countries and cultures: though we may be miles away from our own family and friends, in the local church we quickly discover a new family and new friends, because of the common salvation we have in Christ.
The third great blessing that comes to us in our adoption is the gift of the Spirit of God, whom Paul calls “the Spirit of adoption” in Romans 8:15. It is the indwelling Spirit of God in our hearts who gives us the boldness to cry out “Father” (Rom. 8:15; Gal. 4:6). He bears internal testimony to the reality of our adoption, assuring us that we are indeed God’s children in those times when we are tempted to doubt God’s love for us (Rom. 8:16). He also guides us in the way of righteousness, empowering us to put to death the deeds of the body (Rom. 8:14), adding external marks of our salvation that can further testify to the truth of our adoption. By bearing His fruit in our lives, the Spirit begins to reproduce in us the image of Christ, enabling us increasingly to live as the children of God that He has adopted us to be.
The final great blessing of adoption is the prospect of a glorious inheritance. If we have been adopted into God’s family, then we have become heirs of the family inheritance — heirs of God and co-heirs with Christ, as Romans 8:17 puts it. In Christ, all of the riches of God are ours and will be ours for all eternity. In what, though, does our inheritance consist? After all, Jesus lived on earth in poverty and died penniless, with no possessions to His name. That reality reminds us that bearing the family likeness of Christ in the present will often involve suffering and perhaps even humiliation for the sake of His name. Yet if we suffer with Him, we may be assured that our identification with Christ will culminate in sharing His glory (Rom. 8:17). Those who by grace persevere faithfully to the end are granted a share in the relationship that the Lord promised to David and his sons: to each of them, God declares, “I will be his God and he will be my son” (Rev. 21:7).
The full nature of this future glory as the children of God remains a mystery in the present (1 John 3:2). In some way, it will give to us a radically new likeness to Christ in His glory and holiness. When we see Him, we shall be like Him. Even now, through the Spirit we are being remade into His image, but that work is often frustratingly slow and incomplete. Yet the day will come when God’s work in us will be finished and we will be free from corruption and sin, truly bearing the family likeness. In comparison to this promise, what we have already received in the Spirit’s work within us and the Father’s presence with us is but a shadowy glimpse of our eternal inheritance as the adopted children of the King. On that day, however, we will grasp more fully how great and awesome is God’s grace and mercy to us in Christ, that has redeemed us from Satan’s family and granted us membership in His own family as His treasured sons and daughters.