Two character are introduced in John 3&4.
Nicodemus was a Ruler of the Jews, a Pharisee and a Teacher of Israel. That means he was a student of God’s word and knew it forwards and backwards, inside and out. He came to Jesus with a simple statement… “Rabbi we know that you are a teacher sent from God because no one can do the signs you are doing unless God is with him”.
Jesus, never one to mince words or waste time, cuts to the chase…. “Except one be born again he cannot see the (coming) Kingdom of God.”
You see, Jesus knew who Nicodemus was and knew that Nicodemus knew what was in the Old Testament (from a human perspective). Nicodemus was obedient to the 10 commandments, kept the proper form of worship, kept the Sabbath and feast days properly, etc., etc., etc. Jesus just needed to correct some misconceptions that Nicodemus had about the coming Kingdom.
The second character introduced was different than Nicodemus. She was an un-named Samaritan woman. In contrast to Nicodemus she knew next to nothing about the Old Testament. As a Samaritan all she had been taught and all she knew were the first 5 books of the Bible. Samaritans had improper worship and they didn’t celebrate the Passover properly. The Jews despised them for their corruption of God’s commandments.
Jesus was sitting at a well when the woman approached and asked her for a drink of water. The woman, knowing that Jesus was a Jew, was surprised that he would even acknowledge her presence and was bold enough to state that to him.
Jesus replied, if you knew who I am you could have asked and I would have given you living water. The conversation evolves into the age old question between the Samaritans and the Jews… where is the proper place to worship? Jesus informs her that the Jews are worshipping correctly (and the Samaritans are not) but then proceeds to tell her that a time is coming… the coming of the Kingdom… when neither place will be the correct place to worship.
So we might ask the question… why didn’t Jesus answer the Samaritan woman like he did Nicodemus? Why didn’t he tell her… “except one be born again he cannot enter the Kingdom of God?” And the answer is because they were in different places in their understanding of God’s word
The reality is Jesus taught them both the same basic thing. Both audiences had to believe that in the new Kingdom, citizens would have to worship in Spirit and in Truth, he just took different approaches to accomplish that task.
Of course the same thing is true today. You cannot necessarily teach two individuals the exact same way but we do have to end up in the same place. If we have the idea that we can just quote some passage like Acts 2:38 with the idea of accept it or reject it and feel like we have done our job as a teacher then we are sadly mistaken.
The Gospel is for all including those who know their Bible (but misunderstand it) and for those who know next to nothing about the Bible. As a teacher prepare yourself for every kind of student.