Summa summae S. Thomae, Tomus II

As regards the sin of omission, since it is in itself a mere privation of the act due, it is certain that it is specifically distinguished by the acts themselves omitted specifically distinct in moral being; as all other privations are specifically distinguished by the opposite forms by which they deprive; namely in that manner in which privations can be distinguished. The question is therefore of the sin of commission.

I say: Sins are specifically distinguished by their order to objects specifically distinct in moral being ¹; because every act is specified by its object. Therefore an act morally evil is specified by an object morally evil.

It is confirmed. Every motion is specifically distinguished by order to the term to which. But, in sinful motion, the object is the term to which. Therefore.

This conclusion all Thomists hold with the Author, and many outsiders, even those among the Thomists who place the formal element of sin in the privative; because, they say, with diverse order to formally diverse objects standing, there follows diverse privation.

I said in the conclusion: « By order to objects specifically distinct in moral being; » because the specific distinction of objects in the order of being contributes nothing to the specific distinction of sins; for whether one steals a sheep or a horse, he commits a sin of the same species, namely of injustice. But

The question is whence the object has that it be specifically distinguished in moral being.

I answer. Generally speaking, objects are specifically distinguished in moral being when they have a special and distinct repugnance with the eternal law and right reason. Now they have a special and distinct repugnance or disconformity with the eternal law and right reason from a multiple head: 1° when they are opposed to different virtues; 2° when they are opposed to the same virtue, but in a different way, as is evident in theft and robbery, which although they are opposed to the same virtue of justice, are nevertheless specifically distinguished, because they are opposed to it in a different way; 3° when they are opposed to different precepts, not materially and on the part of the principle or commander, but formally on the part of the thing commanded or intrinsic motive. Whence it can be said that sins are also distinguished specifically, namely radically and mediately, by the virtues and precepts to which they are opposed.

Conclusions

From what has been said you will infer 1° that one who omits Mass on a feast day falling on Sunday, or does not fast on an ember Wednesday falling on the vigil of St. Matthew, commits in each case one sin specifically and numerically, in the first case against religion, in the second against temperance, because both the precept of hearing Mass on Sunday and on a feast day, and both of fasting on ember days and on the vigil of St. Matthew, are of the same account on the part of end and intrinsic motive. For the end and intrinsic motive of hearing Mass on Sunday and a feast day is the honesty of religion, and of the precept of fasting on the ember days and the vigil of St. Matthew, the honesty of temperance. Nor does it matter that perhaps the legislator, in commanding Mass on the day of St. Matthew, or fasting on his vigil, intended to honor the saint; for that end or motive is extrinsic and of the agent, just as if in commanding a fast he intended rain, fair weather, or peace, which ends or extrinsic motives do not constitute precepts of different account. Say the same of one who violates the same vow or oath repeated several times, of omitting the canonical hours to which he is bound by title of benefice and sacred order.

You will infer 2° on the contrary, that one who is bound by vow and the precept of his confessor to fast on the Friday of the ember days, if he does not fast, commits three sins specifically distinct: first, against temperance, by force of the ecclesiastical precept; second, against religion, by force of the vow; third, against the virtue of penance, by force of the precept of the confessor. For these three obligations are from different intrinsic motives, and thus of distinct account; for the intrinsic motive of the ecclesiastical precept is temperance, of the vow is religion, of the precept of the confessor imposing a fast after sins heard, with attention to the nature of the work and the circumstances, is punishment and satisfaction for sins.