Now, putting aside the statements about being born from above and born of water and spirit, what would probably have been more significant for Nicodemus was Jesus’ multiple use of the term “kingdom of God.” This would have been Nicodemus’ concern. It is likely that this is what he was after---that which he desired to see. To that end, he would be asking “Was Jesus the Messiah?” Was He the One through Whom the Creator God of Israel was going to work to usher in His kingdom and set all things right?
As one ponders the thoughts and emotions that these possibilities would have been potentially stirring in Nicodemus, his seemingly ludicrous response about a man entering into his mother’s womb and being born a second time (John 3:4b) almost comes off as an effort to focus on something besides Jesus’ talk about the great Jewish hope, with this being an attempt to obfuscate his own tremendous excitement at what this might very well mean for him, for his people, for their land, and for the world.
The same thing could possibly be said about Nicodemus’ question of “How can these things be?” (3:9a) Remember, Nicodemus was not necessarily there for a theological and philosophical dissertation. He came, based on his relationship with Jesus, for a conversation concerning expectations. He came for information. The Gospel record attempts to make it obvious that Nicodemus wanted to know what Jesus thought about Himself. His concern was the kingdom of God, and whether the God of Israel was now and finally fulfilling His long-standing promise through this man that had quite recently been so incredibly demonstrative at the Temple, and who was said to have done many signs while at the feast of Passover.
This too is significant. Passover is always crucial, and due to the crowds that the celebration would bring to Jerusalem, the events of Passover would regularly be seized upon for those wishing to draw attention to themselves and their causes by making grand, symbolic statements. Thus, one should not lose sight of the fact that the signs to which Nicodemus is referring were being performed by Jesus in association with Passover. Passover, of course, was the yearly celebration of the Creator God intervening on behalf of His oppressed people, conquering their enemies, and leading them out of Egypt (in dramatic confirmation of His promise to Abraham) under the leadership of their great deliverer, Moses.
The juxtaposition of performing signs at Passover, combined with His actions in the Temple, would not have been lost on anybody who was in the least bit culturally and religiously aware, especially a Pharisee who was also a member of the ruling council. A person doing what Jesus was said to have done, in conjunction with the feast that was conducted on an annual basis in celebration of the time when the covenant God gave His people liberation from their oppressors who were keeping them outside of the promised blessings of their God, was effectively declaring that he was, at the least, a messianic figure. This could very well serve to inspire great hope and arouse great passions among a significant portion of the people.
Naturally, this sparking of hope and passion could take different paths. One path would be the establishment of the heaven-come-to-earth kingdom of the God of Israel, through a glorious display of His saving power against the enemies of Israel (not unlike that which was said to have been witnessed by the Egyptians). The other way would be a rebellion that would inevitably result in being crushed by Rome, along with an executed messiah. Accordingly, Nicodemus needed to know more from Jesus. That is why he was there.