From Catechetical Lectures 16:11-12 (ca. 350)
Let us drink from the “living water, welling up to eternal life,” (John 4:10, 14). The savior said this about the Spirit which those who believe in him were to receive. Look at what he says, “the one who believes in me.” But not simply this. He also sends us back to the Old Testament and adds, “as the scripture has said, ‘out of his hearty shall flow rivers of living water” (John 7:38). Jesus is talking not about rivers perceived by the senses which simply water the earth and produced thorns and trees, by rivers which illuminate the soul…
Why did he call this spiritual grace, water? Because water nourishes all things and it produces vitality and life. While rain showers come down from heaven in one form, they work in a variety of ways… So also, the Holy Spirit, being one unique and indivisible reality, gives grace to each one as he wills (1 Cor. 12). Just as the dry tree partakes of water and then sends out its branches, so also, the soul in sin, when it has been made worthy of the Holy Spirit through repentance, produces the fruit of righteousness.
Although one in nature, the Holy Spirit works many virtues by the command of God and in the name of Christ. He uses the tongue of one for wisdom and enlightens the soul of another for prophecy. He gives to one the power to cast out demons, but to another he gives the ability to interpret divine scriptures. He strengthens the chastity of one and teaches another to be merciful… Different things for different people, but not different from the Spirit himself (1 Cor 12:7-11).
St. Cyril of Jerusalem (ca. 313-386) was a theologian and liturgist, who served as Bishop of Jerusalem for nearly forty years. He developed the complex liturgical rites of the Church of the Holy Sepulchre, which influenced Christian worship across the ancient world, as pilgrims from Jerusalem brought home elements of what they had observed. His Catechetical Lectures were given to catechumens early in his episcopate. His feast day is March 18.
