John Chrysostom

What he says seems indeed to involve no small question: but if any one attends to it diligently, this too will admit of an easy solution. What then is the question? It is the saying that through the offence of one many were made sinners. For the fact that when he had sinned and become mortal, those who were of him should be so also, is nothing unlikely. But how would it follow that from his disobedience another would become a sinner? …

Homily on Romans X ↗

Theophylact of Ohrid

Here, it would seem, there is a repetition; but in reality there is none. Above he said (Rom. 5:18): "as by the offense of one judgment came upon all men to condemnation, so by the righteousness of one the free gift came upon all men unto justification," and now he explains what the transgression of the one consisted of, and says that it was disobedience, through which many were made sinners, that is, subject to punishment and condemned to death; he also explains what the righteousness of the One, that is, of Christ, consists of, and …

Commentary on Romans ↗

Irenaeus

For as by one man's disobedience sin entered, and death obtained [a place] through sin; so also by the obedience of one man, righteousness having been introduced, shall cause life to fructify in those persons who in times past were dead. And as the protoplast himself Adam, had his substance from untilled and as yet virgin soil ("for God had not yet sent rain, and man had not tilled the ground"), and was formed by the hand of God, that is, by the Word of God, for "all things were made by Him," and the Lord took dust from the earth and …

Against Heresies Book III ↗

Thomas Aquinas

Then when he says, for as by the disobedience, the Apostle proves the same thing from something prior. For causes are similar to their effects. But the disobedience of the first parent, which bears the character of injustice, made men sinners and unrighteous. Therefore, the obedience of Christ, which bears the character of justice, made them righteous. And this is what he stated previously, namely, that grace proceeds forth into all men to justification. …

Commentary on Romans ↗