Theophylact of Ohrid

And He was under the law, received circumcision, and fulfilled everything, in order to deliver us from the curse to which He Himself was not subject. And he points to two saving effects in the incarnation of Christ: our liberation from the curse of the law and the granting of adoption. And he said "receive" in order to show that adoption was destined for us from of old by promise, although on account of our immaturity it was not given to us. For the inheritance promised to Abraham was adoption. Because a son inherits.

Commentary on Galatians ↗

Oecumenius

"so that we might receive adoption as sons." For he not only freed us from evil, having removed the curse of the law, but also bestowed adoption. And by saying "we might receive" he showed it to be appointed from above, and that we are not able to receive it because of the childishness of our understanding.

Commentary on Galatians ↗

Thomas Aquinas

Then when he says, "that he might redeem them who were under the law," he sets down the fruit of the reality in which the simile is applied, namely, that the reason why He willed they be subject during that time was that they might become heirs great and free. And he mentions both of these things. …

Commentary on Galatians ↗

Bonaventure

Although God could have become incarnate from the beginning, He nevertheless willed not to do so until the end of the ages. After these He deigned to become incarnate as at the end of times and in their fullness, according to what the Apostle says: "But when the fullness of time had come, God sent His Son, made of a woman, made under the Law, that He might redeem those who were under the Law." Since freedom of the will requires that it be drawn to nothing against its will, God ought to have restored the human race in such a way that …

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