This untouchable subject, must be touched. Christ Jesus was after who-so-ever-will; and Jn.3:1-10 shows that Nicodemus was a very important person, leader, in another Religion. This took place at night, and with the patience of dealing with a precious child. Our Creator, always meets us where we are.
"Except a man[mankind] be born again [*from above], he can not SEE the Kingdom of God[YHVH]." From Gen.1:2 we have the beginning of the second-earth-age: this age has designed purpose. All of the children will be born, and given the opportunity to decide Who their Father is. Our worship - is our walk.
"See the Kingdom". This is to perceive with senses; to notice, discern, discover. The Kingdom, is Royal-Power. To be born from above, "of water and The Spirit". We come here 99% complete: it is The Spirit of our Creator that is responsible for Revelation - when we are ready. Many can't see because they have chosen to submit, or follow "Blind Leaders" that lack The Spirit.
We are legal: our Creator, created mankind in "His own Image"[Gen.1:26-31], and it was GOOD! The Spirit was placed in us from the beginning of this age. Our Creator communes, and abide with our spirit, through His Spirit. The fruit? People in the Kingdom do not habitually sin[1Jhn.3:9]. The Light is on[1Jhn.2:29] for those that can discern the fruit.
"That which is born of the flesh is flesh". Flesh = human nature, the earthly nature of man apart from God's [YHVH] influence, prone to sin opposed to God [YHVH]. This applies to Satan, the fallen angels, and the Tares. Not even the Thief can get around-
"You Must born from above".