The Angelic Doctor Against the Errors of the Greeks - Part Two - Chapter 4

That the Son works through the Holy Spirit.

It is also established on the authority of Sacred Scripture that the son works in the Holy Spirit or through the Holy Spirit. The Apostles in Romans 15: 18 says: For I will not venture to speak of anything except what Christ has wrought through me to win obedience from the Gentiles, by word and deed, by the power of signs and wonders, by the power of the Holy Spirit. And in 1 Cor. 2:10 it is said: God has revealed them through his Spirit. For he is the Spirit of the Father and the Son. Hence the Father and the Son work in revealing through the Holy Spirit.

This is why Athanasius says in the letter to Serapion: “The Son of God, by enlightening us in going before us and by justifying us in strengthening our faith and by unlocking the Scriptures in filling us with the gifts of wisdom, bestows his gifts while he forgives sin and endows us with his charisms, not in the spirit of another not his own, but in his own Holy Spirit.”  And Cyril also says in his discourse on the dogmas of God: “The Son has by essence in himself the Holy Spirit as his own and as naturally sent from him; in him he has worked divine miracles as by his own true and proper power.” 

From the fact that the Son works through the Holy Spirit it is necessarily concluded that the Holy Spirit is from the Son. Someone may be said to work through another in two ways. One way, in so far as that by which one works is a principle unto itself and cause of the operation, either as the efficient and moving cause, as the bailiff is said to work through the king; or as the formal cause, as man is said to work through his art. The other way, in so far as that by which one works is a cause in relation to the work and not to the agent, as the king is said to work through his baliff and the artist through his instrument. In this case the one working must contrariwise be called the principle of the operation in relation to that by which the operation is accomplished, as the king in relation to that by which the operation is accomplished, as the king in relation to the bailiff or the artist in relation to the instrument he uses.

When, therefore, it is said that the Son works through the Holy Spirit, the Holy Spirit cannot be understood to be the principle of operation in relation to the Son, since the Son does not receive from the Holy Spirit. The only alternative, then, is that the Son is the principle of operation in relation to the Holy Spirit. And this cannot be except on this basis that he give him his operative power. But he does not give this to him as though he had it not previously, for this would imply that the Holy Spirit lacked it and so would be less than the Son. Hence, the only alternative is that he give it to him from eternity. Nor is the operative power of the Holy Spirit anything else than his essence, since the Holy Spirit, like the Father, is simple. Hence, the only alternative is that the Son give the divine essence to the Holy Spirit from eternity.

And Athanasius says this expressly in his letter to Serapion: “As the Father naturally works through the Son and in the Son originating from him and not contrariwise, so the Son naturally works in the Holy Spirit originating from him as in his own power, and not contrariwise.”