The Son of God who was to end the legal bondage, was sent into it Himself. He wore the legal yoke that He might break it. He took "the form of a servant," to win our enfranchisement. "God sent forth His Son, human, law-bound--that He might _redeem those under law_." Redemption was Christ's errand. We have learned already how "He redeemed us from the curse of the law," by the sacrifice of the cross (ch. iii. 13). This was the primary object of His mission: to ransom men from the guilt of past sin. Now we discern its further purpose--the positive and constructive side of the Divine counsel. Justification is the preface to _adoption_. The man "under law" is not only cursed by his failure to keep it; he lives in a servile state, debarred from filial rights. Christ "bought us out" of this condition. While the expiation rendered in His death clears off the entail of human guilt, His incarnate life and spiritual union with believing men sustain that action, making the redemption complete and permanent. As enemies, "we were reconciled to God by the death of His Son;" now "reconciled, we shall be saved by His life" (Rom. v. 10). Salvation is not through the death of Christ alone. The Babe of Bethlehem, the crowned Lord of glory is our Redeemer, as well as the Man of Calvary. The cross is indeed the centre of His redemption; but it has a vast circumference. All that Christ is, all that He has done and is doing as the Incarnate Son, the God-man, helps to make men sons of God. The purpose of His mission is therefore stated a second time and made complete in the words of ver. 5 _b_: "that we might _receive the adoption of sons_." The sonship carries everything else with it--"if children, then heirs" (ver. 7). There is no room for any supplementary office of Jewish ritual. That is left behind with our babyhood. 2. So much for the ground of sonship. Its proof lay in the _sending forth of the Spirit of the Son_.