I've seen 3 explanations for that verse. What is the waters?
Some say the water is a reference to amniotic fluid from the womb. I never agreed with that.
Some say the water is in reference to baptismal waters. I never agreed with that....as water baptism is never expressed by water only. Some say it refers to the waters of Johns baptism.
Some say the water is in reference to the Holy Spirit. You must be born again...from above. Baptism waters don't come from above. The Spirit does.
5 Jesus answered, “Truly, truly, I tell you, no one can enter the kingdom of God unless he is born of water and the Spirit. 6 Flesh is born of flesh, but spirit is born of the Spirit.
The bottom line....there is no hard conclusion that can be drawn from this verse as to what the water is.
What is typically over looked in this passage is the timeline, and the person Jesus was speaking to.
1. This conversation took place around A.D. 27, around the same time as the wedding in Cana. This around the start of Jesus' ministry. The point
is, Christian baptism had not been instituted until a later date. In Oneness terms, "Jesus name baptism was instituted in Acts 2 (A.D. 30).
2. Who is Nicodemus?
Joh 3:1 Now there was a man of the Pharisees, named Nicodemus, a ruler of the Jews;
Joh 3:10 Jesus answered and said to him, “You are the teacher of Israel, and yet you do not understand these things?
The question I would ask Kade is this. If Nicodemus is "the" teacher of Israel, what would he have known about Christian baptism?
Jesus also used the Definite article, indicating that Nicodemus was not simply one of many teachers, but "The teacher of Israel."
As the teacher of Israel, he was well versed in the OT scripture. So whatever Jesus was asking him would have been something he should have known from the Hebrew text. The bottom line, Jesus was not referencing water baptism.