Chapter 47 — That the Spirit, which is in God, is holy

It must also be considered that since the good that is loved has the character of an end, and since the motion of the will is rendered good or evil by the end it pursues, the love whereby the supreme good that is God is loved must possess the supereminent goodness that goes by the name of holiness. This is true whether ‘holy’ is taken as equivalent to ‘pure,’ in accord with the Greeks (since in God there is most pure goodness free from all defect), or whether ‘holy’ is taken to mean ‘firm,’ in accord with the Latins (since in God there is unchangeable goodness). In either case, everything dedicated to God is called holy, such as a temple, and the vessels of the temple, and all objects consecrated to divine service. Rightly, then, the Spirit, who represents to us the love whereby God loves himself, is called the Holy Spirit. For this reason the rule of Catholic faith names the Spirit ‘Holy,’ when it says, I believe in the Holy Spirit.