John Calvin wrote that Spirit of Adoption was the Holy Spirit’s “first title.” That is, of all the ways in which the Scriptures refer to the Holy Spirit, Spirit of Adoption is his greatest, or first, title. If one considers the transformation of dead sinners into beloved children of God as the Spirit’s greatest work then Calvin was certainly right. Paul’s words concerning our adoption as sons are among the greatest words of consolation and assurance to be found anywhere in the Bible. And having been adopted we are heirs of God and fellow heirs with Christ.
Being an heir of God means that the love the Father has for the Son from eternity is now lavished upon us. But being an heir also means that we wait for the full experience of our inheritance. While being adopted sons of God places Christians within the realm of eternal life it also places them squarely in the already-not-yet of this present age. Christians are new creations in Christ, adopted by God and saved unto eternal life while simultaneously living in an evil age of sin and death.
From the very beginning, Christians have often found themselves living in societies that marginalize, misunderstand, and even punish them for their commitment to Christ. And this is why Paul’s words to the Roman church continue to comfort every generation of Christians. In this world we will suffer for the name of Christ. But not even the world’s cruelest mistreatment can undo the glory of our adoption by the Spirit. Indeed, the glory of the Kingdom of God is gained as we participate in Christ which includes joining him in his suffering.