John Chrysostom

"For as many as are led by the Spirit of God, they are the sons of God." Now this is again a much greater honor than the first. And this is why he does not say merely, As many as live by the Spirit of God, but, "as many as are led by the Spirit of God," to show that he would have Him use such power over our life as a pilot doth over a ship, or a charioteer over a pair of horses. And it is not the body only, but the soul itself too, that he is for setting under reins of this sort. …

Homily on Romans 14 ↗

Theophylact of Ohrid

Above he gave such a promise: you shall live if you put to death wicked deeds. Now he offers a most important crown and a greater reward, namely adoption by God. He did not say: all who live by the Spirit, but all who are led by the Spirit, that is, who are governed as by a charioteer, making the Spirit master over soul and flesh. Although you received baptism and became through baptism a son of God, yet if you are not led by the Spirit, you will lose the gift. …

Commentary on Romans ↗

Cyprian

If we are the sons of God, if we have already begun to be his temples, if (after receiving the Holy Spirit) we live holily and spiritually, if we have lifted up our eyes from the earth toward heaven, if we have raised our hearts, full of God and Christ, to supernal and divine things, let us do nothing which is not worthy of God and Christ, as the apostle arouses and urges us.

Treatise X. On Jealousy and Envy 14 ↗

Gregory the Dialogist

For in the Law God held the rod, in that He said, 'If any man do this or that, let him die the death.' But in His Incarnation He removed the rod, in that He shewed the paths of life by mild means. Whence it is said to Him by the Psalmist, "Set forward, go forth prosperously and rejoice, because of truth, and meekness, and righteousness." For He had no mind to be feared as God, but put it into our hearts that as a Father He should be loved; as Paul clearly delivers; "For ye have not received the Spirit of bondage again to fear, but ye …

Morals on the Book of Job, Book 9 ↗

Thomas Aquinas

After stating that the life of glory, which will exclude all mortality from our bodies, will be given to us through the Holy Spirit, the Apostle now proves this. First, he shows that this glorious life is given by the Holy Spirit; second, why it is deferred, at "yet so, if we suffer with him." In regard to the first he presents this argument: all who are sons of God obtain the inheritance of a glorious life; but those who are ruled by the Holy Spirit are sons of God. …

Commentary on Romans ↗