The born-again teaching's importance is emphasized by Jesus' introduction of the doctrine by proclaiming, "Verily, verily"—or "Truly, truly," "Most assuredly," or "Amen, amen," depending on the translation. All of His "Verily, verily" statements appear in the book of John, and they are used by Christ only when He is about to teach on a profound matter. The doubled "verily" denotes that what follows is of especially weighty and solemn significance, so we are to pay special attention.
It is evident from Nicodemus' words as he approaches Jesus that he desires to be taught and has a readiness to hear. He acknowledges that Jesus has been sent by God and offers that His miracles are evidence that God is with Him. Even so, it seems to him as if Jesus speaks to him in a foreign language.
The Jews call Jesus' statement in John 3:3 a mashal, a difficult saying. Nicodemus is obviously puzzled by its intent. The interesting thing is what triggers Nicodemus' response. If he understood some of the ramifications of Jesus' statement that "unless one is born again, he cannot see the kingdom of God," he would realize that even he, a Jew of high position, was already disqualified unless he met the requirement of being born again! That would have been shocking to one so highly placed and regarded.
John W. Ritenbaugh
Born Again or Begotten? (Part One)