"Except a man be born again, he cannot see the kingdom of God."
John 3:3 · King James Bible
The story
Nicodemus is a Pharisee and a member of the Sanhedrin — the ruling council of the Jews. John calls him "a ruler of the Jews" (John 3:1). He appears three times in the fourth Gospel, and each time he is closer to Christ than the last.
First — by night (John 3). He comes to Jesus after dark, drawn by the miracles but afraid of his fellow rulers. "Rabbi, we know that thou art a teacher come from God." Jesus answers before the question is even asked: "Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God." Nicodemus struggles: "How can a man be born when he is old?" Jesus says the wind blows where it lists, and gives him the sentence that has been the summary of the whole Gospel ever since: "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" (John 3:16).
Second — in the council (John 7:50–52). The chief priests are conspiring to arrest Jesus. Nicodemus speaks up — carefully, procedurally: "Doth our law judge any man, before it hear him, and know what he doeth?" It is the smallest possible defence — the defence of due process — but in that room, at that moment, it costs him something. They mock him: "Art thou also of Galilee?"
Third — at the cross (John 19:38–42). After the crucifixion Joseph of Arimathea comes to Pilate and asks for the body of Jesus. Nicodemus comes with him — no longer at night — bringing "a mixture of myrrh and aloes, about an hundred pound weight." That is a kingly burial spice, in a kingly quantity. Together they wrap the body of the Lord in linen with the spices and lay him in a new tomb.
Why he matters
Nicodemus is Scripture's most patient portrait of a slow conversion. He does not become a disciple all at once. He comes by night. He speaks up quietly. And at last he stands openly at the tomb with a hundred pounds of spice. The Christian tradition (both East and West) honours him as a saint. He is a comfort to every household that has a family member or a friend who is being drawn to Christ, slowly.
Where to read
John 3:1–21 · John 7:45–52 · John 19:38–42 (KJV).