Humanity’s adoption by God as his children is a theme throughout Hebrew and Christian scripture. By his own free will God has chosen Israel and the Church established on her foundation to be his children. God’s adoption of humankind gives theological richness to what it means for people to be in relationship to God, to live a life of holiness, and to be free.
Relationship
Throughout Scripture, God is time and time again referenced as Israel and Christians’ father and parent. In Isaiah the prophet praises God on behalf of the remnant of Israel declaring “thou, O LORD, art our Father” (Isa 63:16, ʀꜱᴠ). In Jeremiah 31:9 God says that he is “a father to Israel” (ʀꜱᴠ). In Galatians 4:6 Paul teaches that believers are God’s children — sons — and that we should call God “father.” Jesus, too, teaches this when he demonstrates to his followers how to pray, “Our Father who art in heaven, ” “Father, hallowed be thy name” (Matt 6:9-13, Luke 11:2-4).
Focusing on Isa 63:16 as representative parent language for God is instructive for a soteriological understanding of adoption. First, as with Matt 6:9, God is the faithful community’s father — “our father.” Our is a key word here. God is, through adoption, not a single individual’s parent alone; he is the father of the community of all who are in Jesus. Though we are adopted individually, God deals with us as his, plural, children.
As made clear in the RSV and other translations/languages that retain a personal and formal second person pronoun, the language for God the Father in Scripture uses the personal pronoun used within families and close friendships. Through God’s choosing, humanity has entered a familial relationship with God. We are now his children and, as children of a common parent, humanity has entered a filial association within the community of believers. Through Christ, in our relationship to God the Father, the members of the community are now literally siblings to each other.
“Sonship” — the status of being a child of a parent — has been eternally experienced by Jesus. Triune sonship, however, has eternally included the deep unity and love of Father and Spirit. Just as Jesus is the Father’s son, so too are those who accept Jesus as Messiah. As Jesus laid his life into the Father’s hands (Luke 23:46) the faithful community’s entering into the faith of Jesus brings with it the care of the Father’s hands. God the Father is not only the executor of justice but through the faith of Jesus the source of parental care and love that conquers death. For God to call and accept us as children — sons —, means the faithful community has been invited into the very life of God. Adoption means participation in the triune love of Father, Son, and Holy Spirit.
Holiness
A key point of any theology of salvation is to answer the question from what humanity is being saved from or for. In the Hebrew Bible, God initiates covenants with Israel to give them a system of remaining in right relation to him, with each other, and with their neighbor. Through the Fall, humankind has entered into the reality of enmity to God and the death that broken relationship brings. We are living out of covenant with God, both because those who were given the law do not fully live it and because not all were given the law — gentiles.
God, as the source of life and existence, adopts all who show faith like Abraham into his family (Rom 4:16-18). Without God’s law given in covenant to Israel and fulfilled and lived within the community of his Church, humanity has no path to cleanse the impurities inherited from Adam from our lives. Living a life in the hope and faith of Jesus will lead humanity to a state of purity and holiness like unto God (1 John 3:3). God, through the adoption made possible in Jesus Christ, adopts us into his covenant and laws to guide us towards this life of holiness. Holiness before God and in relationship to each other brings us salvation because living God’s life leads us to a close, familial relationship with him. We must be inside the life of God, the source of life itself, to escape death.
In baptism and Hebrew circumcision, God marks us as his own and claims us for his enteral life of triune love. Without the holiness and purity found in the law and living the faith of Jesus, humanity would find itself lacking the qualities needed for unity with God. God has adopted us as children to give us a path and a means to be “holy and blameless before him” (Eph 1:4 ʀꜱᴠ). He “destined us in love to be his sons [children] through Jesus Christ” (Eph 1:5 ʀꜱᴠ). Outside of relationship with God, humanity cannot experience the “love the Father has given us” (1 John 3:1 ʀꜱᴠ) which is the very essence of Godhood and that which is and binds the Trinity together and “unite[s] all things in him” (Eph 1:3-10 ʀꜱᴠ). God is both the source and the goal of our salvation.
Freedom
Holiness through the law given by God to those adopted in faith is not only the path towards a relationship of loving unity with God, but humanity’s path towards freedom. Outside of the life exemplified in the life of Jesus and Torah, humanity is enslaved by the “elemental spirits of the universe” (Gal 4:3 ʀꜱᴠ). At enmity with the Source of Life, humanity is bound by the fears of death and scarcity. All of creation is in “bondage to decay” (Rom 8:21 ʀꜱᴠ) and enslaved to gather and store what can be had to sustain life before it fades away. Through adoption, however, humanity is freed from slavery to death and scarcity by becoming children and heirs of God (Gal 4:7); the eternal and limitless source of all life, material, and immaterial things. In union with God there is no death and no scarcity, but life and abundance; humanity obtains “the glorious liberty of the children of God” (Rom 8:21 ʀꜱᴠ). Freed from fears of giving out of our own scarcity and instead relying on the limitless supply of God’s gifts, humanity can fully live into the freely gifting life of God. Here trust is built, love is learned, and relationship with God extended and refined. Adoption means full freedom to love God without boundaries or fears; it means to live under the guardianship of God into the promises afforded an heir.
Conclusion
Adoption is a beautiful symbol for salvation because it focuses on the loving, eternally stable, gifting life of Father, Son, and Holy Spirit. To be adopted is take on the name and identity of a family. To be adopted requires an actor and initiator outside of oneself. Adoption into the family of God brings the faithful a stable community of divine love where instruction is given, love is unconditional, and one is able to fully live into the humanity God created in his own image.