The doctrine of adoption plays a major role in Calvin’s tracts, letters, sermons, Institutes, and most importantly, his commentaries. Timothy Trumper states on this matter, “It is increasingly apparent that the commentaries are indispensable to an appreciation of Calvin’s theology of adoption.” When one considers Calvin’s development of adoption he begins by stating that it is motivated by the Father’s electing grace in Christ. This is best seen through Calvin’s own words:
“It is not from a perception of anything that we deserve, but because our heavenly Father has introduced us, through the privilege of adoption, into the body of Christ. In short, the name of Christ excludes all merit, and everything which men have of their own; for when he says that we are chosen in Christ, it follows that in ourselves we are unworthy.”
Calvin saw that adoption was designed for the glory of God, in that those saved by the gospel are then to live for the glory of God in holiness, purity, and doing every deed in obedience to honor their heavenly Father. To Calvin, adoption was not just a blessing; he knew that the privileges that were given to the believer upon the act of adoption came with responsibilities. Calvin saw adoption not only as a promised inheritance for believers, but also as a way in which believers are to think, live, and transform their new life according to the Word of God.
Quotes take from; Dr. Timothy Trumper, “An Historic Study of the Doctrine of Adoption in the Calvinistic Tradition” on page 47 and John Calvin, Calvin’s Commentaries on Ephesians, page 198.