Summa Theologica, Part I · Aquinas Thomas
QUESTION 39
According to the fourth consideration, i.e. God's relation to His effects, there arise[s] appropriation of the expression "from Whom, by Whom, and in Whom." For this preposition "from" [ex] sometimes implies a certain relation of the material cause; which has no place in God; and sometimes it expresses the relation of the efficient cause, which can be applied to God by reason of His active power; hence it is appropriated to the Father in the same way as power. The preposition "by" [per] sometimes designates an intermediate cause; thus we may say that a smith works "by" a hammer. Hence the word "by" is not always appropriated to the Son, but belongs to the Son properly and strictly, according to the text, "All things were made by Him" (John 1:3); not that the Son is an instrument, but as "the principle from a principle." Sometimes it designates the habitude of a form "by" which an agent works; thus we say that an artificer works by his art. Hence, as wisdom and art are appropriated to the Son, so also is the expression "by Whom." The preposition "in" strictly denotes the habitude of one containing. Now, God contains things in two ways: in one way by their similitudes; thus things are said to be in God, as existing in His knowledge. In this sense the expression "in Him" should be appropriated to the Son. In another sense things are contained in God forasmuch as He in His goodness preserves and governs them, by guiding them to a fitting end; and in this sense the expression "in Him" is appropriated to the Holy Ghost, as likewise is "goodness." Nor need the habitude of the final cause (though the first of causes) be appropriated to the Father, Who is "the principle without a principle": because the divine persons, of Whom the Father is the principle, do not proceed from Him as towards an end, since each of Them is the last end; but They proceed by a natural procession, which seems more to belong to the nature of a natural power.
Regarding the other points of inquiry, we can say that since "truth" belongs to the intellect, as stated above (Q. 16, A. 1), it is appropriated to the Son, without, however, being a property of His. For truth can be considered as existing in the thought or in the thing itself. Hence, as intellect and thing in their essential meaning, are referred to the essence, and not to the persons, so the same is to be said of truth. The definition quoted from Augustine belongs to truth as appropriated to the Son. The "book of life" directly means knowledge but indirectly it means life. For, as above explained (Q. 24, A. 1), it is God's knowledge regarding those who are to possess eternal life. Consequently, it is appropriated to the Son; although life is appropriated to the Holy Ghost, as implying a certain kind of interior movement, agreeing in that sense with the property of the Holy Ghost as Love. To be written by another is not of the essence of a book considered as such; but this belongs to it only as a work produced. So this does not imply origin; nor is it personal, but an appropriation to a person.
Ideas discussed in this chapter
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