Nicodemus means conqueror of the people; some give it a Hebrew derivation which means innocent blood.
Nicodemus was an important man, a Jewish leader which means he was probably a member of the Sanhedrin, the highest governing body of the Jewish people. The Sanhedrin consisted of 70 members who were mostly Sadducees. Nicodemus was one of the few Pharisees among these leaders.
This man came to Jesus by night and said to him, “Rabbi, we know that you are a teacher come from God, for no one can do these signs that you do unless God is with him.” (John 3:2 ESV)
Nicodemus did not only speak for himself but on the behalf of others. Nicodemus, the teacher of Israel, addressed Jesus as Rabbi, the same title Nicodemus’ disciples would address him as. Nicodemus was thereby acknowledging Jesus as Master and placing himself in the position of a student.
Nicodemus confirmed that they knew Jesus was a Teacher and that Jesus was sent from God, because the signs Jesus did could only come from God. In other words they said Jesus was not only a teacher but a teacher with divine authority.
Jesus went to the heart of the matter and told Nicodemus that he must be born again to see the kingdom of God. The kingdom of God was a topic Jesus taught a lot about. The Gospel accounts are full of references to the kingdom of God, with the most accounts in the book of Matthew. Although the kingdom of God is only mentioned twice in the book of John, in John 3:2 and when Jesus teaches about the beatitudes in Matthew 5, John refers often to eternal life which is part of the meaning of the kingdom of God.
Nicodemus was stuck in the physical realm and could not understand how a person that has already been born could be born again. Nicodemus was familiar with rebirth for Gentiles who were proselytes to Judaism, but not that Jews had to be reborn. He did not understand the difference between a second birth and a different birth, because he did not realize Jesus was talking about a spiritual birth. Jesus explains to Nicodemus by telling him that the process of being born again is by water and Spirit. In other words, you are born physical as a human being, and then by Spirit when you accept Jesus Christ as your Saviour. Jesus uses a physical example, namely the wind to explain this mystery to Nicodemus.
Jesus confirmed that He spoke the truth; that He spoke of what He had witnessed; but still many do not accept what He says and do not believe in Him.
Jesus answered him, “Are you the teacher of Israel and yet you do not understand these things? Truly, truly, I say to you, we speak of what we know, and bear witness to what we have seen, but you do not receive our testimony. If I have told you earthly things and you do not believe, how can you believe if I tell you heavenly things? No one has ascended into heaven except he who descended from heaven, the Son of Man. (John 3:10-13 ESV)
Rebirth was earthly things. The heavenly things Jesus spoke about were that Jesus had descended from heaven with His incarnation and that after the cross and His resurrection He would ascend into heaven.
Numbers 21:4-9 tells us that in the wilderness Israel were bitten by poisonous snakes because they murmured against God. When they came to Moses for help, God instructed him to make a bronze snake, place it on a pole and lift it up so whoever saw this would be healed. Jesus would be lifted up on the cross to die for our sins. The Israelites received physical life, but Jesus’ death on the cross would bring spiritual life, eternal life, to all who believed in Him.
“For God loved the world so much that he gave his one and only Son, so that everyone who believes in him will not perish but have eternal life. God sent his Son into the world not to judge the world, but to save the world through him.
“There is no judgment against anyone who believes in him. But anyone who does not believe in him has already been judged for not believing in God’s one and only Son. And the judgment is based on this fact: God’s light came into the world, but people loved the darkness more than the light, for their actions were evil. All who do evil hate the light and refuse to go near it for fear their sins will be exposed. But those who do what is right come to the light so others can see that they are doing what God wants.*” (John 3:16-21 NLT)
Read more about Holy Spirit – Holy Spirit the Person series.