What does John 7:39 mean?
On the last and most important day of the Feast of Booths, Jesus chose a dramatic time to make a dramatic point. On this day, priests would carry water into the temple, remembering God's provision of water from a rock (Exodus 17:1–7). Jesus uses this moment to emphasize His claim to being the source of "living water." That is a metaphor for salvation and the indwelling of the Holy Spirit. Jesus has used this theme before, both publicly (John 6:35), and in private (John 4:10–14). Later New Testament passages will continue to draw from this analogy when describing the salvation offered by God through Christ (Ephesians 5:26; Revelation 22:1–2).At the time Jesus spoke these words, the Holy Spirit worked selectively in the world. Among the more dramatic examples of the Holy Spirit's temporary work is in the story of Samson, who was given strength when the Holy Spirit was within him (Judges 14:6). Only after Jesus' death and resurrection, followed by His ascension, will the Holy Spirit begin to indwell everyone who professes faith in Christ (Acts 2:1–4; Ephesians 1:13–14).
John 7:37–52 shows how Jesus' public ministry challenges the traditional views of Judaism. This causes infighting among both the people and the Jewish leaders themselves. The people hear His words, see His miracles, and begin to wonder if Jesus really is the Promised One. Once again, the religious leaders attempt to arrest Jesus, but the officers are so impressed by His words that they leave Him alone. When Nicodemus, a Pharisee, makes a plea for due process, he is mocked and his suggestion is ignored. Moments such as this will eventually lead the Jewish leaders to extreme measures against Jesus.
Six months after the feeding of thousands, and the public debate which followed, Jesus plans to attend the Feast of Booths, also called the Festival of Tabernacles. Rather than going publicly, He chooses to arrive privately, and after His family. While teaching and preaching there, Jesus once again comes into conflict with local religious leaders. The crowds take note of His profound words, history of miracles, and the inability of the religious leaders to silence Him. This causes the people to openly question their spiritual leaders. This embarrassment is a milestone in the effort to permanently silence Jesus.