Reply Obj. 1: The aspect of good is found chiefly in the end: and therefore the end stands in the relation of object to the act of the will which is at the root of every sin. Consequently it amounts to the same whether sins differ by their objects or by their ends.
Reply Obj. 2: Sin is not a pure privation but an act deprived of its due order: hence sins differ specifically according to the objects of their acts rather than according to their opposites, although, even if they were distinguished in reference to their opposite virtues, it would come to the same: since virtues differ specifically according to their objects, as stated above (Q. 60, A. 5).
Reply Obj. 3: In various things, differing in species or genus, nothing hinders our finding one formal aspect of the object, from which aspect sin receives its species. It is thus that pride seeks excellence in reference to various things; and avarice seeks abundance of things adapted to human use. ________________________
SECOND ARTICLE [I-II, Q. 72, Art. 2]
Whether Spiritual Sins Are Fittingly Distinguished from Carnal Sins?
Objection 1: It would seem that spiritual sins are unfittingly distinguished from carnal sins. For the Apostle says (Gal. 5:19): "The works of the flesh are manifest, which are fornication, uncleanness, immodesty, luxury, idolatry, witchcrafts," etc. from which it seems that all kinds of sins are works of the flesh. Now carnal sins are called works of the flesh. Therefore carnal sins should not be distinguished from spiritual sins.
Obj. 2: Further, whosoever sins, walks according to the flesh, as stated in Rom. 8:13: "If you live according to the flesh, you shall die. But if by the spirit you mortify the deeds of the flesh, you shall live." Now to live or walk according to the flesh seems to pertain to the nature of carnal sin. Therefore carnal sins should not be distinguished from spiritual sins.
Obj. 3: Further, the higher part of the soul, which is the mind or reason, is called the spirit, according to Eph. 4:23: "Be renewed in the spirit of your mind," where spirit stands for reason, according to a gloss. Now every sin, which is committed in accordance with the flesh, flows from the reason by its consent; since consent in a sinful act belongs to the higher reason, as we shall state further on (Q. 74, A. 7). Therefore the same sins are both carnal and spiritual, and consequently they should not be distinguished from one another.
Obj. 4: Further, if some sins are carnal specifically, this, seemingly, should apply chiefly to those sins whereby man sins against his own body. But, according to the Apostle (1 Cor. 6:18), "every sin that a man doth, is without the body: but he that committeth fornication, sinneth against his own body." Therefore fornication would be the only carnal sin, whereas the Apostle (Eph. 5:3) reckons covetousness with the carnal sins.
On the contrary, Gregory (Moral. xxxi, 17) says that "of the seven capital sins five are spiritual, and two carnal."