What does John 7:28 mean?
It's hard to tell if Jesus is being serious or sarcastic in His statement that the people "know Him." On one hand, they are aware of His family and His hometown of Nazareth. On the other hand, that familiarity has led many to dismiss Him as the Messiah. In addition, most of these people do not accept Jesus' ministry, or His teachings, as they should. This remark is in response to a suggestion made by some in the crowd: that Jesus cannot be the Promised One since they know where He is from. Messiah, according to their assumptions, should be more anonymous.Jesus' second statement in this verse is much easier to classify. This is a direct criticism of Israel's spiritual state, and an extremely personal reproach. Israel's ultimate point of pride was its identity as God's chosen people. No other nation could make that claim—and here, Jesus tells God's chosen people that they do not know God! Their rejection of God (John 5:39–40) has resulted in a rejection of the One sent by God (John 6:29). Stubbornness and pride have made them resistant to the truth (John 7:17).
As expected, this accusation does not go over well with the people or the religious authorities. Neither does Jesus' claim, from the next verse, that He possesses both divinity and godly approval.
John 7:25–36 is a milestone in the plot to kill Jesus. Jesus continues to criticize the local religious leaders, who are unable to successfully arrest Him. This leads the people to wonder: are the scribes and Pharisees in agreement with Jesus or too weak to stop Him? That crisis of confidence will make the Jewish leaders more convinced that they need to silence Jesus at all costs. Even so, misinterpreting His comments in the passage presents a possible solution: if Jesus is going somewhere they cannot follow, perhaps the problem will resolve itself.
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.