On the contrary, Origen says [*Peri Archon i, 3]: "I think that a man who stands on the highest step of perfection cannot fail or fall suddenly: this can happen only by degrees and little by little." Now our first parents were established on the highest and perfect grade. Therefore their first sin was not the greatest of all sins.
I answer that, There is a twofold gravity to be observed in sin. one results from the very species of the sin: thus we say that adultery is a graver sin than simple fornication. The other gravity of sin results from some circumstance of place, person, or time. The former gravity is more essential to sin and is of greater moment: hence a sin is said to be grave in respect of this gravity rather than of the other. Accordingly we must say that the first man's sin was not graver than all other sins of men, as regards the species of the sin. For though pride, of its genus, has a certain pre-eminence over other sins, yet the pride whereby one denies or blasphemes God is greater than the pride whereby one covets God's likeness inordinately, such as the pride of our first parents, as stated (A. 2).
But if we consider the circumstances of the persons who sinned, that sin was most grave on account of the perfection of their state. We must accordingly conclude that this sin was most grievous relatively but not simply.
Reply Obj. 1: This argument considers the gravity of sin as resulting from the person of the sinner.
Reply Obj. 2: The severity of the punishment awarded to that first sin corresponds to the magnitude of the sin, not as regards its species but as regards its being the first sin: because it destroyed the innocence of our original state, and by robbing it of innocence brought disorder upon the whole human nature.
Reply Obj. 3: Where things are directly subordinate, the first must needs be the greatest. Such is not the order among sins, for one follows from another accidentally. And thus it does not follow that the first sin is the greatest. _______________________
FOURTH ARTICLE [II-II, Q. 163, Art. 4]
Whether Adam's Sin Was More Grievous Than Eve's?
Objection 1: It would seem that Adam's sin was more grievous than Eve's. For it is written (1 Tim. 2:14): "Adam was not seduced, but the woman being seduced was in the transgression": and so it would seem that the woman sinned through ignorance, but the man through assured knowledge. Now the latter is the graver sin, according to Luke 12:47, 48, "That servant who knew the will of his lord . . . and did not according to his will, shall be beaten with many stripes: but he that knew not, and did things worthy of stripes, shall be beaten with few stripes." Therefore Adam's sin was more grievous than Eve's.
Obj. 2: Further, Augustine says (De Decem Chordis 3 [*Serm. ix; xcvi de Temp.]): "If the man is the head, he should live better, and give an example of good deeds to his wife, that she may imitate him." Now he who ought to do better, sins more grievously, if he commit a sin. Therefore Adam sinned more grievously than Eve.