Commentaria in Summam contra Gentiles, Liber IV

Having shown that the Holy Spirit is, it remains to show what he is¹. Concerning this, St. Thomas does three things²: first, he shows that he is true God; second, that he proceeds from the Son, in chapter xxiv.

Concerning the first he does three things: first, he brings forward the arguments from which some have thought the Holy Spirit to be a creature; second, he determines the truth, in the following chapter; third, he answers the objections, in chapter xxiii.

As to the first, he says that some were of the opinion that the Holy Spirit is a creature more excellent than others, and that they wished to confirm this by the testimonies of Sacred Scripture.

First, because in Amos 4 it is said, according to the Septuagint text, Behold, he that formeth the mountains and createth the spirit, etc. And Zech. 12: Thus saith the Lord, who stretcheth forth the heavens, etc.

Second, because in John 16 he seems to be set forth as a creature that serves God, when it is said: He shall not speak of himself, etc.

Third, because he is sent by the Father and the Son: as is shown when it is said, John 14, The Paraclete, the Holy Spirit, etc.; and 15, When the Comforter is come, etc.

Fourth, because Scripture, associating the Son with the Father in those things which seem to belong to divinity, makes no mention of the Holy Spirit: as in Matt. 11, No one knoweth, etc.; and John 17, This is life eternal, etc.; and Rom. 1, Grace to you, etc.; and 1 Cor. 8, To us there is but one God, etc.

Fifth, Scripture attributes motion to the Holy Spirit, Gen. 1, The Spirit of God, etc.; and Joel 2, I will pour out, etc. Therefore etc.

Sixth. The Holy Spirit can be increased, diminished, and changed. Therefore etc. — The antecedent is proved. Because the Lord says, Num. 11, to Moses, Gather unto me, etc.; and in 4 Kings, Elisha asked of Elijah, I beseech thee, etc.

Seventh. Grief falls upon the Holy Spirit. Eph. 4, Grieve not; and Isa. 63, They provoked to wrath, etc. Therefore etc.

Eighth. It belongs to the Holy Spirit to pray: Rom. 8, The Spirit himself, etc. Therefore etc.

Ninth. The Father and the Son give the Holy Spirit. Luke 11, Your Father, etc. And in Acts 5 it is said that God gave the Holy Spirit, etc. Therefore etc.

Tenth. If he is God, he has the divine nature. And since he proceeds from the Father, it is necessary that he receive the divine nature from him. And thus it follows that he is begotten, and consequently a son. Which is repugnant to the faith.

Eleventh. It follows that the divine nature is communicated in two ways: namely, in the way in which the Son proceeds, and in the way in which the Holy Spirit proceeds. But this does not seem to belong to one nature, that it be communicated in two ways. Therefore etc.

Lastly, St. Thomas adds that this was the position of Arius, positing both the Son and the Holy Spirit to be less than the Father, yet the Son greater than the Holy Spirit. — Macedonius also followed him as regards the Holy Spirit: whence also some call the Macedonians Semi-Arians.