Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God.
That is the Scriptural way.
On the other hand, Protestants do not read Scripture the Scriptural way:
2 Corinthians 3:6
Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.
They read Scripture literally and thus miss the Spiritual teachings contained in the Word of God:
1 Corinthians 2:14
But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned.