Speaking of Noah, our unerring Scriptures tell us that he “was a just and perfect man in his generation,” meaning that he was perfect as far as citizens of the city of God can be perfect during the pilgrimage of this present life, not, of course, as perfect as they are to be in that immortal life in which they will be as perfect as the angels of God.
Grace. Notwithstanding the general denunciation against all flesh, we see here that God will not confound the just with the guilty, in the same punishment. Noe pleased God, by observing the most perfect justice, in the midst of a corrupt generation. (St. Chrysostom;) (Worthington)
Therefore, in praise of Noah, Scripture not merely called him “blameless” but added “among the men of his day” to make it clear that he was so at that time when the obstacles to virtue were many. Besides, other men were illustrious after him, yet he will have no less praise than they. For he was blameless in his own time.
Do you see how the Lord created our nature to enjoy free will? I mean, how did it happen, tell me, that while those people showed enthusiasm for wickedness and rendered themselves liable to punishment, this man opted for virtue, shunned association with them and thus felt no effect of punishment? Is it not crystal clear that each person chose wickedness or virtue of his own volition? You see, if that were not the case and freedom did not have its roots in our nature, those people would not have been punished, nor would others receive reward for their virtue. Since, however, everything has been allowed to remain with our choice owing to grace from on high, punishment duly awaits the sinners, and reward and recompense those who practice virtue.
The Scriptures have shown us the gravity of human wickedness and the severity of the punishment that had to be inflicted on it. They then point out to us the one who amid such a multitude had been able to keep a sincere virtue. Virtue in fact is admirable even for itself. If someone cultivates virtue among those who refuse it, he makes it much more worthy of admiration. Therefore the Scriptures, as though in admiration of this just man, point out the contrast: that only one man who was living among those who soon would experience the wrath of God, this Noah, “found favor in the eyes of the Lord God.” He “found favor,” but “in the eyes of God”; not simply “he found favor” but “in the eyes of the Lord God.” This is said in order to show us that he had a single purpose, that is, to be praised by that eye that never sleeps or rests. He had no care for human glory or scorn or irreverence.