Patristic Wisdom: Looking to the Third Sunday in Lent

Whoever drinks of this water will thirst again, but whoever drinks of the water that I shall give him will never thirst. But the water that I shall give him will become in him a fountain of water springing up into everlasting life. (Jn 4:10–14)

Let then this much suffice concerning those outcasts; and now let us return to the divine Scriptures, and let us drink waters out of our own cisterns and out of our own springing wells. We drink of living water, springing up into everlasting life; but the Savior spoke this of the Spirit, which they that believe on Him should receive. For observe what He says: He that believes on Me (not simply this, but), as the Scripture has said (thus He has sent you back to the Old Testament), out of his belly shall flow rivers of living water, not rivers perceived by sense, and merely watering the earth with its thorns and trees, but bringing souls to the light. And in another place He says: But the water that I shall give him, shall be in him a well of living water springing up into everlasting life—a new kind of water living and springing up, springing up unto them who are worthy.

Cyril of Jerusalem, Catechetical Lectures 16.11

Jesus shows the incomparable difference that there is between spiritual water and earthly perceptible water by saying, “Everyone who drinks of this water will thirst again.” But those who have their fill of my water, He says, not only will be raised beyond ever thirsting again but also will have in themselves a spring that is able to nourish them to eternal life. The one who gives greater gifts is greater, He says, than the one who has less, and the one who is inferior will not come away with the same glory as the one who conquers.

Next we must realize that the Savior here calls the grace of the Holy Spirit “water.” If anyone should become a participant of it, they will then have a supply of divine knowledge springing up in them so that they no longer need admonition from others. Instead they will be sufficient and capable to exhort with ease those who thirst for the divine and heavenly word. These were the saints, prophets, and apostles during their lives while they were still living here on earth, and the heirs of their service, concerning whom it is written, “Draw water with joy from the springs of salvation.” [Is 12:3]

Cyril of Alexandria, Commentary on John 4.14