Nicodemus could not understand how a man could be born when he is old, so Jesus explained that it was a spiritual birth. "That which is born of the flesh is flesh, and that which is born of the spirit is spirit." And as the wind softly stirred the leaves of the olive trees above their heads He said,
"The wind bloweth where it listeth, and thou hearest the sound thereof, but canst not tell whence it cometh and whither it bloweth. So is every one that is born of the Spirit."
Nicodemus had always thought that religion was the keeping of the law as all Jews were taught by the priests, so he was astonished, and said,
"How can these things be?"
"Art thou a master in Israel and knowest not these things?" said Jesus, and then He spoke to the soul of Nicodemus of the things of the Spirit of Heaven—The Heaven in which He already lived,—and of the new kingdom that had begun on earth.
If you will find what Jesus said to Nicodemus in the third chapter of John's Gospel you will find among other things these beautiful words,—
"For God so loved the world that he gave His only begotten Son, that whosoever believeth in Him should not perish, but have everlasting life."
Nicodemus found out that life was the breath of God in man, and that by it man lives. Perhaps he felt it within him as he went down the valley under the trees and heard the wind among the leaves; and as he came up the steep way and through the city gate in the silence of the night, perhaps he resolved to be a disciple of Jesus.