In this passage from John, Jesus speaks of living water not just as water, but also as a symbol for the Holy Spirit and what is to come after Jesus’ death and resurrection for his followers who believe in Him. See, there are certain things we can receive from just one source: there is no substitute, no dupe, no knockoff, no duplicate. We receive Life from God and we receive that which sustains us spiritually from God—this is this Living Water. The work of the Holy Spirit.