ADOPTION. An act by which one takes another into his family, owns him for his son, and appoints him his heir. The Greeks and Romans had many regulations concerning adoption. It does not appear that adoption, properly so called, was formerly in use among the Jews. Moses makes no mention of it in his laws; and the case of Jacob’s two grandsons, Gen. xlviii, 14, seems rather a substitution.
2. Adoption in a theological sense is that act of God’s free grace by which, upon our being justified by faith in Christ, we are received into the family of God, and entitled to the inheritance of heaven. This appears not so much a distinct act of God, as involved in, and necessarily flowing from, our justification; so that, at least the one always implies the other. Nor is there any good ground to suppose that in the New Testament the term adoption is used with any reference to the civil practice of adoption by the Greeks, Romans, or other Heathens, and therefore it is not judicious to illustrate the texts in which the word occurs by their formalities. The Apostles in using the term appear to have had before them the simple view, that our sins had deprived us of our sonship, the favour of God, and the right to the inheritance of eternal life; but that, upon our return to God, and reconciliation with him, our forfeited privileges were not only restored, but greatly heightened through the paternal kindness of God. They could scarcely be forgetful of the affecting parable of the prodigal son; and it is under the same view that St. Paul quotes from the Old Testament, “Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean thing, and I will receive you, and I will be a Father unto you, and ye shall be my sons and daughters, saith the Lord Almighty.”
Adoption, then, is that act by which we who were alienated, and enemies, and disinherited, are made the sons of God, and heirs of his eternal glory. “If children, then heirs, heirs of God and joint heirs with Christ;” where it is to be remarked, that it is not in our own right, nor in the right of any work done in us, or which we ourselves do, though it should be an evangelical work, that we become heirs; but jointly with Christ, and in his right.