Q: Whether the Unnatural Vice Is the Greatest Sin Among the Species of Lust?

A: On the contrary,
Augustine says (De adult. conjug. [*The quotation is from Cap. Adulterii xxxii, qu. 7. Cf. Augustine, De Bono Conjugali, viii.]) that "of all these," namely the sins belonging to lust, "that which is against nature is the worst."

I answer that,
In every genus, worst of all is the corruption of the principle on which the rest depend. Now the principles of reason are those things that are according to nature, because reason presupposes things as determined by nature, before disposing of other things according as it is fitting. This may be observed both in speculative and in practical matters. Wherefore just as in speculative matters the most grievous and shameful error is that which is about things the knowledge of which is naturally bestowed on man, so in matters of action it is most grave and shameful to act against things as determined by nature. Therefore, since by the unnatural vices man transgresses that which has been determined by nature with regard to the use of venereal actions, it follows that in this matter this sin is gravest of all. After it comes incest, which, as stated above (A. 9), is contrary to the natural respect which we owe persons related to us.

With regard to the other species of lust they imply a transgression merely of that which is determined by right reason, on the presupposition, however, of natural principles. Now it is more against reason to make use of the venereal act not only with prejudice to the future offspring, but also so as to injure another person besides. Wherefore simple fornication, which is committed without injustice to another person, is the least grave among the species of lust. Then, it is a greater injustice to have intercourse with a woman who is subject to another's authority as regards the act of generation, than as regards merely her guardianship. Wherefore adultery is more grievous than seduction. And both of these are aggravated by the use of violence. Hence rape of a virgin is graver than seduction, and rape of a wife than adultery. And all these are aggravated by coming under the head of sacrilege, as stated above (A. 10, ad 2).

Reply Obj. 1: Just as the ordering of right reason proceeds from man, so the order of nature is from God Himself: wherefore in sins contrary to nature, whereby the very order of nature is violated, an injury is done to God, the Author of nature. Hence Augustine says (Confess. iii, 8): "Those foul offenses that are against nature should be everywhere and at all times detested and punished, such as were those of the people of Sodom, which should all nations commit, they should all stand guilty of the same crime, by the law of God which hath not so made men that they should so abuse one another. For even that very intercourse which should be between God and us is violated, when that same nature, of which He is the Author, is polluted by the perversity of lust."

Reply Obj. 2: Vices against nature are also against God, as stated above (ad 1), and are so much more grievous than the depravity of sacrilege, as the order impressed on human nature is prior to and more firm than any subsequently established order.

Reply Obj. 3: The nature of the species is more intimately united to each individual, than any other individual is. Wherefore sins against the specific nature are more grievous.

Reply Obj. 4: Gravity of a sin depends more on the abuse of a thing than on the omission of the right use. Wherefore among sins against nature, the lowest place belongs to the sin of uncleanness, which consists in the mere omission of copulation with another. While the most grievous is the sin of bestiality, because use of the due species is not observed. Hence a gloss on Gen. 37:2, "He accused his brethren of a most wicked crime," says that "they copulated with cattle." After this comes the sin of sodomy, because use of the right sex is not observed. Lastly comes the sin of not observing the right manner of copulation, which is more grievous if the abuse regards the "vas" than if it affects the manner of copulation in respect of other circumstances.

QUESTION 155

OF CONTINENCE (In Four Articles)

We must next consider the potential parts of temperance: (1) continence; (2) clemency; (3) modesty. Under the first head we must consider continence and incontinence. With regard to continence there are four points of inquiry:

(1) Whether continence is a virtue?

(2) What is its matter?

(3) What is its subject?

(4) Of its comparison with temperance.