The promise is quite audacious. It was both a proclamation, made to a thirsty woman at a well during mid-day, and a pledge, that common well-water would never satisfy. Completely. His promise was different, because He alone would provide a Living Water, and whoever partakes of it would never thirst again, also becoming a fountain of living water, welling up from within into everlasting life.
Fifth Sunday of Pascha: The Samaritan Woman
So He came to a city of Samaria which is called Sychar, near the plot of ground that Jacob gave to his son Joseph. Now Jacob's well was there. Jesus therefore, being wearied from His journey, sat thus by the well. It was about the sixth hour. A woman of Samaria came to draw water. Jesus said to her, "Give Me a drink."
For His disciples had gone away into the city to buy food. Then the woman of Samaria said to Him, "How is it that You, being a Jew, ask a drink from me, a Samaritan woman?" For Jews have no dealings with Samaritans. Jesus answered and said to her, "If you knew the gift of God, and who it is who says to you, 'Give Me a drink,' you would have asked Him, and He would have given you living water." The woman said to Him, "Sir, You have nothing to draw with, and the well is deep.
Where then do You get that living water?
Are You greater than our father Jacob, who gave us the well, and drank from it himself, as well as his sons and his livestock? Jesus answered and said to her, "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. The woman said to Him, "Sir, give me this water, that I may not thirst, nor come here to draw." Jesus said to her, "Go, call your husband, and come here." The woman answered and said, "I have no husband." Jesus said to her, "You have well said, 'I have no husband,' for you have had five husbands, and the one whom you now have is not your husband; in that you spoke truly. The woman said to Him, "Sir, I perceive that You are a prophet. Our fathers worshiped on this mountain, and you Jews say that in Jerusalem is the place where one ought to worship. Jesus said to her,
"Woman, believe Me, the hour is coming when you will neither on this mountain, nor in Jerusalem, worship the Father. You worship what you do not know; we know what we worship, for salvation is of the Jews. But the hour is coming, and now is, when the true worshipers will worship the Father in spirit and truth; for the Father is seeking such to worship Him. God is Spirit, and those who worship Him must worship in spirit and truth. The woman said to Him, "I know that Messiah is coming" (who is called Christ). "When He comes, He will tell us all things." Jesus said to her, "I who speak to you am He." And at this point His disciples came, and they marveled that He talked with a woman; yet no one said, "What do You seek?" or, "Why are You talking with her?"
The woman then left her waterpot, went her way into the city, and said to the men, Come, see a Man who told me all things that I ever did. Could this be the Christ?
Then they went out of the city and came to Him. In the meantime His disciples urged Him, saying, "Rabbi, eat." But He said to them, "I have food to eat of which you do not know." Therefore the disciples said to one another, "Has anyone brought Him anything to eat?" Jesus said to them, "My food is to do the will of Him who sent Me, and to finish His work. Do you not say, 'There are still four months and then comes the harvest'? Behold, I say to you, lift up your eyes and look at the fields, for they are already white for harvest! And he who reaps receives wages, and gathers fruit for eternal life, that both he who sows and he who reaps may rejoice together. For in this the saying is true: 'One sows and another reaps.' I sent you to reap that for which you have not labored; others have labored, and you have entered into their labors. And many of the Samaritans of that city believed in Him because of the word of the woman who testified, "He told me all that I ever did." So when the Samaritans had come to Him, they urged Him to stay with them; and He stayed there two days. And many more believed because of His own word. Then they said to the woman,
Now we believe, not because of what you said, for we ourselves have heard Him and we know that this is indeed the Christ, the Savior of the world."
The Holy Gospel According to St. John the Theologian Chapter 4 verses 5-42
Commentary - Saint Theophan the Recluse
The Samaritan’s woman fellow citizens said to her after two days with the Savior in their midst, Now we believe not because of thy saying: for we have heard him ourselves, and know that this is indeed the Christ, the Savior of the world (John 4:42). It happens this way with everyone. At first they are called to the Lord by an external word, or as for many now, simply by birth. But when they taste in practice what it is to live in the Lord, they no longer cleave to the Lord through their external affiliation with Christian society, but through their inner union with Him. It is necessary for all who are born in Christian societies to make this a law for themselves; that is, to not limit themselves to mere external affiliation with the Lord, but to seek to unite with Him inwardly, that they may always bear witness within themselves that they are standing in the truth. Why is this necessary? It is necessary to embody within oneself the truth of Christ. The truth of Christ is a restoration of what is fallen. Thus, put off the old man, which is corrupt according to deceitful lusts, and put on the new man, which is created after God in righteousness and true holiness (cf. Eph. 4:22–24), and you will know within yourself that the Lord Jesus Christ is in truth the Savior—not only for the world, but also for you.