the explanation

Jesus answered, “I assure you and most solemnly say to you,
unless one is born of water and the Spirit he cannot [ever]
enter the kingdom of God. That which is born of the flesh is flesh
[the physical is merely physical], and that which is born of the Spirit is spirit.

Do not be surprised that I have told you,
‘You must be born again [reborn from above—spiritually transformed,
renewed, sanctified].’ The wind blows where it wishes and you hear its sound,
but you do not know where it is coming from and where it is going;
so it is with everyone who is born of the Spirit.””
‭‭John‬ ‭3:5-8‬ ‭(AMP‬‬)