Because of the different Greek word usages between Nicodemus and our Lord, it is beneficial for us to glean, in part, their meanings as they spoke them to see the disparity between Nicodemus' mind set and Christ's lesson.

"MAN" = anthropos, a human being. It is the same word found in vs.4 & 19 which refers to "more than one man," or implies "all men." It is not the same word found in vs.3 & 5 which are spoken by Christ: tis, meaning "some one," or "a certain one." As an example, see Mark 14:51 where it is used with "a certain young man." In other instances when a writer introduces a specific (certain) character, or group, this word is also used, e.g., "a certain noble man," "certain Pharisees," "a certain rich man," etc. Therefore, in our text, man, or anthropos, in specific Nicodemus, is used as representative of all men who come to Christ in private inquiry, and Christ receiving and speaking to each individually as he comes.

TRUTH:
CHRIST, WHO IS THE LIGHT OF THE WORLD, HAS NOW APPEARED TO ALL WHO LIVE IN DARKNESS THAT ALL MIGHT COME TO HIM, BUT EACH MUST BE RECEIVED BY HIM PERSONALLY. (This is the message of the gospel as revealed by Christ.)

"KNOW" = oida, "to see," or "have seen."
This is limited knowledge derived from evidence seen. It refers specifically to the miracles previously performed by Jesus, as identified being the source by Nicodemus himself.

"TEACHER" = didasklos, "instructor."
In this case, "having come from God," indicating absolute knowledge in contrast to Nicodemus' limited knowledge from his source of personal observations. This explains his coming to Jesus: it was this distinction in knowledge detected and noted by Nicodemus that drew him to seek out its higher source for further enlightenment.

"SEE" = eidon, "to be acquainted," "to know."
"See the kingdom of God." The implication is to be "familiar with," "perceive," or "understand."

"ENTER" = eiserchoma, "to come, or go into."
"Enter the kingdom of God." In the above case, Jesus was saying that only those who are "born again" can perceive, or see, the kingdom (in other words, only the regenerated of spirit can perceive the spiritual kingdom Christ has come to establish, which explains why Nicodemus cannot yet discern it, and anyone of any day). Now Jesus is saying, only those who are "born again" can enter, or go into it when it comes to them. Therefore, to the critics of the exclusivity of Christianity as the only way into eternal life, it was Jesus who first declared it so. Peter will echo this truth in his Spirit-inspired message before the state authorities on this Council after Pentecost. It is not something, then, to be backed away from when challenged by today's modern politically correct, liberal, multicultural, secular society.
(More will be said of this in conclusion.)

"WATER AND SPIRIT" This will be discussed in Ch.4.

"BORN" = gennao, "to beget," "bring forth."
"AGAIN" = anothen, "from above."
This is the same word for "above" found in 3:31; 19:11; Js.1:17; and Js.3:15 & 17. It is used exclusively in these places. Peter uses anagennao, "to beget, anew," in his writing of I Pe.1:23. Hence, we can say: "To be born from above, anew!" Through Adam, ALL men died spiritually; through Christ, ALL may be REBORN, born again, to live again AS BEFORE -- forever and eternally.

NOTICE:
the emphasis in these references is upon it being a gift from above (key vs. Js.1:17). Paul declares it as such in Ep.2:8,9, and Jesus says that He is the Gift in 3:16. Therefore, He is the Eternal Life. All who have Him have Eternal Life. Read His declaration to a grieving Mary concerning her brother's destiny. Again Paul says: It is no longer I that lives, but Christ who lives in me. It is so simple yet so profound that no other intelligence is capable of conceiving or counterfeiting it. It is rooted within the unsearchable mysteries of God.

"MUST" = dei, "it behoveth," or "being necessary."
This is the same word used by Christ in vs.14. Again the imperativeness of rebirth is emphasized here. As certain as it was for Jesus to be crucified in order that He be resurrected from death, it is equally important that one embrace Him as the source for new life. There is no other way. As it was not optional for Him to go to the Cross, it is not optional for any one to enter Life except through Him. He is the Door, and if attempted entry in any other fashion, Jesus declares that person a thief and fraudulent. His words in His Revelation, to this John, declares that these will have no part in His new kingdom.

TRUTH:
BEING BORN AGAIN, FROM ABOVE, ANEW, IS NOT MANDATORY FOR EVERYONE, BUT IS NECESSARY FOR ANY ONE WHO WISHES TO ESCAPE THIS LIFE WITH THEIR SOUL ALIVE. (It was not mandatory for Christ to be lifted up for His Redemption, but it was necessary for our salvation. He could have chosen not to, but because of His love, He chose to take our place -- 10:17-18.)

"YE" = humas, "you," "yourselves."
A plural pronoun in both English and Greek. Therefore, it does not refer to Nicodemus alone, but implies his associates and the anthropos, "ALL MEN" of vs.1. The necessity of rebirth is not only for Nicodemus, but for his associates and ALL descendants of the first Adam who are spiritually dead in sin. Jesus is plainly saying to Nicodemus: "Take this message back to your peers."

"WIND" = pneuma, Spirit.
This Greek word is found only here for "wind" in the New Testament. It is the same word translated as "Spirit" in vs.5. It is not anemos, which is translated as "wind" in all other instances, e.g., in Rev.7:1 that refers to the "four winds." Therefore, this is a direct reference to the operations of the Holy Spirit in moving one into Salvation. It is a mystery; no one knows upon whom He will move next. At every point (as with the water above), Jesus uses what Nicodemus is most familiar and turns him to a more deeper meaning of the Spirit. So, an analogy can be seen here with the wind Nicodemus (and we ourselves) may be familiar with.
Think on these:

a.	We do not know from whence it comes or next it goes.
b.	It cannot be seen, only sensed or felt.
c.	It sometimes is a gentle breeze, and at others, a hurricane. (Respectively, Nathanael and Saul's conversion experiences illustrate this.)
d.	It renews and destroys (roots are made stronger).
e.	It brings airborne seed to fertile soil.
f.	It brings gentle rains in times of need and refreshing.
g.	It awakens the slumbering creature and creation.
h.	It fans a tiny spark into a raging flame.
i.	It cleanses and purifies the contaminated space about us for our benefit.
j.	It is the source by which the creature soars!
k.	IT IS MYSTERIOUS! What an Awesome God!

Continue with your own inspirations. Nicodemus' words ends with vs.9. Jesus has allowed him enough words for his own recognition of his inability to comprehend. Jesus will now continue (notice the use of "verily, verily" in each of these instances in John) a discourse of instruction that is one of the richest passages in all the New Testament in revealing God's intent to man and man's own need in response. He will speak many Heavenly truths and life's lessons (too many for our short study here). Confidently I say, if these were the only words ever recorded of Him, they are sufficient for anyone, all, in any generation to understand enough to act upon for eternal security.

The scripture and history are silent as to Nicodemus' response in this meeting with the Master, but based on our previous discussion, one can assume, unlike his peers on many occasions, Jesus' words found their way into both his mind and heart. This we can safely assume.