Why These Properties Are Called Notions

These five properties can be called notions of the persons, for the reason that the distinction between the persons in God is brought to our notice through them. On the other hand, they cannot be called properties, if the root meaning of a property is insisted on, so that a property is taken to mean a characteristic pertaining to one individual alone; for common spiration pertains to the Father and the Son. But if the word “property” is employed in the sense of an attribute that is proper to some individuals as setting them off from others, in the way that “two-footed,” for example, is proper to man and bird in contradistinction to quadrupeds, there is nothing to prevent even common spiration from being called a property. Since, however, the persons in God are distinguished solely by relations, and distinction among the divine persons is manifested by the notions, the notions must in some sense pertain to relationship. But only four of the notions are real relations, whereby the divine persons are related to one another. The fifth notion, innascibility, pertains to relation as being the denial of relation; for negations are reduced to the genus of affirmations, and privations are reduced to the genus of habits, as, for example, not man is reduced to the genus of man, and not white is reduced to the genus of whiteness.

We should note that among the relations whereby the divine persons are related to one another, some have definite names, such as paternity and filiation, which properly signify relationship. But others lack a definite name: those whereby the Father and the Son are related to the Holy Spirit, and the Holy Spirit is related to them. So for these we use names of origin in place of relative names. We perceive clearly that common spiration and procession signify origin, but not relations that follow origin. This can be brought out in the case of the relations between the Father and the Son. Generation denotes active origin, and is followed by the relation of paternity; and nativity signifies the passive generation of the Son, and is followed by the relation of filiation. In like manner, some relation follows common spiration, and the same is true of procession. But as these relations lack definite names, we use the names of the actions instead of relative names.

Reference

St. Thomas Aquinas. (1265-1274). Compendium Theologiae: Why These Properties Are Called Notions, trans. by Cyril Vollert. St. Louis & London: B. Herder Book Co., 1947

All scripture is given by inspiration of God and is profitable for doctrine, reproof, correction, and instruction in righteousness (2 Timothy 3:16).

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