Reply Obj. 2:  In God’s law, the necessity for various affirmative and negative precepts, was that men might be gradually led to virtue, first by abstaining from evil, being induced to this by the negative precepts, and afterwards by doing good, to which we are induced by the affirmative precepts.  Wherefore the affirmative and negative precepts do not belong to different virtues, but to different degrees of virtue; and consequently they are not, of necessity, opposed to sins of different species.  Moreover sin is not specified by that from which it turns away, because in this respect it is a negation or privation, but by that to which it turns, in so far as sin is an act.  Consequently sins do not differ specifically according to the various precepts of the Law.

Reply Obj. 3:  This objection considers the material diversity of sins.  It must be observed, however, that although, properly speaking, negation is not in a species, yet it is allotted to a species by reduction to the affirmation on which it is based. ________________________

SEVENTH ARTICLE [I-II, Q. 72, Art. 7]

Whether Sins Are Fittingly Divided into Sins of Thought, Word, and
Deed?

Objection 1:  It would seem that sins are unfittingly divided into sins of thought, word, and deed.  For Augustine (De Trin. xii, 12) describes three stages of sin, of which the first is “when the carnal sense offers a bait,” which is the sin of thought; the second stage is reached “when one is satisfied with the mere pleasure of thought”; and the third stage, “when consent is given to the deed.”  Now these three belong to the sin of thought.  Therefore it is unfitting to reckon sin of thought as one kind of sin.

Obj. 2:  Further, Gregory (Moral. iv, 25) reckons four degrees of sin; the first of which is “a fault hidden in the heart”; the second, “when it is done openly”; the third, “when it is formed into a habit”; and the fourth, “when man goes so far as to presume on God’s mercy or to give himself up to despair”:  where no distinction is made between sins of deed and sins of word, and two other degrees of sin are added.  Therefore the first division was unfitting.

Obj. 3:  Further, there can be no sin of word or deed unless there precede sin of thought.  Therefore these sins do not differ specifically.  Therefore they should not be condivided with one another.

On the contrary, Jerome in commenting on Ezech. 43:23, says:  “The human race is subject to three kinds of sin, for when we sin, it is either by thought, or word, or deed.”

I answer that, Things differ specifically in two ways:  first, when each has the complete species; thus a horse and an ox differ specifically:  secondly, when the diversity of species is derived from diversity of degree in generation or movement:  thus the building is the complete generation of a house, while the laying of the foundations, and the setting up of the walls are incomplete species, as the Philosopher