The book
11 Nor, again, was it without a reason that he dried the fleece of the Jews, and put the dew from it into a basin, so that it was filled with water, yet he did not himself wash his feet in that dew. The prerogative of so great a mystery was to be given to another. He was being waited for Who alone could wash away the filth of all. Gideon was not great enough to claim this mystery for himself, but “the Son of Man came not to be ministered unto, but to minister.” Let us, then, recognize in Whom these mysteries are seen to be accomplished. Not in holy Gideon, for they were still at their commencement. Therefore the Gentiles were surpassed, for dryness was still upon the Gentiles, and therefore did Israel surpass them, for then did the dew remain on the fleece.
12. Let us come now to the Gospel of God. I find the Lord stripping Himself of His garments, and girding Himself with a towel, pouring water into a basin, and washing the disciples' feet. That heavenly dew was this water, this was foretold, namely, that the Lord Jesus Christ would wash the feet of His disciples in that heavenly dew. And now let the feet of our minds be stretched out. The Lord Jesus wills also to wash our feet, for He says, not to Peter alone, but to each of the faithful: “If I wash not your feet you will have no part with Me.”
13. Come, then, Lord Jesus, put off Your garments, which You put on for my sake; be stripped that You may clothe us with Your mercy. Gird Yourself for our sakes with a towel, that You may gird us with Your gift of immortality. Pour water into the basin, wash not only our feet but also the head, and not only of the body, but also the footsteps of the soul. I wish to put off all the filth of our frailty, so that I also may say: “By night I have put off my coat, how shall I put it on? I have washed my feet, how shall I defile them?”
14. How great is that excellence! As a servant, You wash the feet of Your disciples; as God, You send dew from heaven. Nor do You wash the feet only, but also invitest us to sit down with You, and by the example of Your dignity dost exhort us, saying: “You call Me Master and Lord, and you do well, for so I am. If, then, I the Lord and Master have washed your feet, you ought also to wash one another's feet.”
15. I, then, wish also myself to wash the feet of my brethren, I wish to fulfil the commandment of my Lord, I will not be ashamed in myself, nor disdain what He Himself did first. Good is the mystery of humility, because while washing the pollutions of others I wash away my own. But all were not able to exhaust this mystery. Abraham was, indeed, willing to wash feet, but because of a feeling of hospitality. Gideon, too, was willing to wash the feet of the Angel of the Lord who appeared to him, but his willingness was confined to one; he was willing as one who would do a service, not as one who would confer fellowship with himself. This is a great mystery which no one knew. Lastly, the Lord said to Peter: “What I do you know not now, but shall know hereafter.” This, I say, is a divine mystery which even they who wash will enquire into. It is not, then, the simple water of the heavenly mystery whereby we attain to be found worthy of having part with Christ.
16. There is also a certain water which we put into the basin of our soul, water from the fleece and from the Book of Judges; water, too, from the Book of Psalms. It is the water of the message from heaven. Let, then, this water, O Lord Jesus, come into my soul, into my flesh, that through the moisture of this rain the valleys of our minds and the fields of our hearts may grow green. May the drops from You come upon me, shedding forth grace and immortality. Wash the steps of my mind that I may not sin again. Wash the heel of my soul, that I may be able to efface the curse, that I feel not the serpent's bite on the foot of my soul, but, as You Yourself hast bidden those who follow You, may tread on serpents and scorpions with uninjured foot. You have redeemed the world, redeem the soul of a single sinner.
17. This is the special excellence of Your loving-kindness, wherewith You have redeemed the whole world one by one. Elijah was sent to one widow; Elisha cleansed one; You, O Lord Jesus, have at this day cleansed a thousand. How many in the city of Rome, how many at Alexandria, how many at Antioch, how many also at Constantinople! For even Constantinople has received the word of God, and has received evident proofs of Your judgment. For so long as she cherished the Arians' poison in her bosom, disquieted by neighbouring wars, she echoed with hostile arms around. But so soon as she rejected those who were alien from the faith she received as a suppliant the enemy himself, the judge of kings, whom she had always been wont to fear, she buried him when dead, and retains him entombed. How many, then, have You cleansed at Constantinople, how many, lastly, at this day in the whole world!
18. Damasus cleansed not, Peter cleansed not, Ambrose cleansed not, Gregory cleansed not; for ours is the ministry, but the sacraments are Yours. For it is not in man's power to confer what is divine, but it is, O Lord, Your gift and that of the Father, as You have spoken by the prophets, saying: “I will pour out of My Spirit upon all flesh, and their sons and their daughters shall prophesy.” This is that typical dew from heaven, this is that gracious rain, as we read: “A gracious rain, dividing for His inheritance.” For the Holy Spirit is not subject to any foreign power or law, but is the Arbiter of His own freedom, dividing all things according to the decision of His own will, to each, as we read, severally as He wills.
Source: On the Holy Spirit (New Advent)