Joh 19:28 After this, Jesus, knowing that all was now finished, said (to fulfill the Scripture), "I thirst."
Far from being merely an historical account of Jesus’ death, the Gospels recount these events in such a way to explain what is going on spiritually. John alone omits the three hours of darkness as Jesus hung on the cross but he is the only to tell us that Jesus said “I thirst” after the three hours of darkness. Why does Jesus call out only minutes before he gives up his life that he is thirsty? Was it necessary for him to get a drink and then die? I think the word “thirst” is significant.
When someone is thirsty we might say that it is because they have exerted some sort of work and are weary because of it. I think this is the point here. He was doubtless thirsty three hours before but it is here that he proclaims his thirst. His thirst right after his great work of making atonement for sin, of bearing the wrath of God, of suffering the effects of the curse points to the fact that he has done some great work and is therefore thirsty. This comes right after the three hours of darkness when he suffers the separation from the Father as the Father’s wrath is poured out on him. This is specifically the work of substitutionary atonement in which he does the work that we could not do for ourselves.
He told the woman at the well that if she would believe in him or drink from spiritual water she shall never thirst again. How can he keep this promise? Because he in his death has provided eternal life, he became thirsty by doing a work that we could not do so that we would never thirst like he did that day. He took our shame, pain, death, punishment, abandonment, Hell, burden, all the futility and all the unfilled desires that sin brings. He suffered the abandonment of God so that we never will have to.
The Samaritan woman’s thirst, not just physically but spiritually would be continuous because she had no way to gain life in herself. Hell is eternal for this very reason. Sin will always leave us wanting because to be separated from God is to never be fulfilled, never happy, never satisfied, totally ruined. Only in Jesus’s work can sin be atoned for and our “thirst” be satisfied.
I am glad that one day Jesus was thirsty so that someday I never will be in need of anything again.