Ambrosiaster : There is no doubt that one adopts a son in order to leave him an heir; but inheritance depends on the death of someone. How then can mortals be called the heirs of him who lives forever? The fact is that Scripture speaks in our own manner so that we may understand. In order to show that the Father will give from his goods those things that he is going to give his sons, it calls this "inheritance." — EPISTLE TO THE Galatians 4.7 Clement of Alexandria : "So also we, when we were children, were in bondage under the rudiments of the world: but when the fulness of the time was came, God sent forth His Son, made of a woman, made under the law, to redeem them that were under the law, that we might receive the adoption of sons" by Him. See how He has admitted those to be children who are under fear and sins; but has conferred manhood on those who are under faith, by calling them sons, in contradistinction from the children that are under the law: "For thou art no more a servant," he says, "but a son; and if a son, then an heir through God." What, then, is lacking to the son after inheritance? — The Instructor Book 1 Jerome : What we say in this place we should also observe in others, that the whole human race is being treated under a single term. For all we who believe are one in Christ Jesus and members of his body. — EPISTLE TO THE Galatians 2.4.7 Jerome : (Verse 7) So then, you are no longer a slave but a son. And if a son, then an heir through Christ. And because you are sons, God has sent the Spirit of his Son into our hearts, crying, 'Abba! Father!' So you are no longer a slave, but a son, and if a son, then an heir through God. Ask of me and I will give you the nations for your inheritance, and the ends of the earth for your possession (Psalms 2:7-8). But what we say in this place, we should also observe in other cases, that in the whole human race, discussions should be conducted in the singular number. For all believers, we are one in Christ Jesus, and members of his body, and brought into a perfect man, who is our head, for the head of the man is Christ (1 Corinthians 11:2). — Commentary on Galatians