By nature, fallen humans cannot participate in God’s eternal kingdom, Jesus says, unless they are born again from above (John 3:3). We must move from religion to relationship, from head to heart, from church to Christ. We must be regenerated with a new nature to become a new life-form. Nicodemus had come to Jesus at night (v.2) and spiritually also he was in the dark. “How can this be?” he asked, thinking in literal, fleshly terms. Jesus explained: “Truly, truly, unless one is born of water and the Spirit, he cannot enter into the kingdom of God” (v. 5). What does Jesus mean? Three possibilities have been suggested, all summed up by a fourth.
Nicodemus might have thought of Ezekiel’s ancient prophecy of a time when God would renew his people from the inside. “Then I will sprinkle clean water on you …. I will cleanse you …. I will give you a new heart and put a new spirit within you …. I will put my Spirit within you …. So you will be my people and I will be your God” (Ezek. 36:25-27). To Ezekiel long ago, God promised to give his future people a new nature, symbolized by water (cleansing) and by Spirit (transformation).
Nicodemus the rabbi and Pharisee might also have remembered the words of John the Baptist, who said: “I baptize in water” (John 1:26) but pointed to Jesus as the one “who baptizes in the Holy Spirit” (v. 33). John contrasted “water” — the outward symbol, and “Spirit” — the inward reality. Even if Nicodemus had received water baptism from John, that was not enough. He must look to Jesus for inward renewal and a new nature.
Nicodemus would not have thought of Christian baptism for Jesus had not yet instituted it, but every original reader of John’s Gospel probably did make that connection. For gospel baptism also involves these two elements — water on the outside and Spirit on the inside — and the first is ineffective without the second (Titus 3:5). Divorced from spiritual regeneration within, dipping in water is only a physical wetting. Where living faith is present, however, this ritual powerfully proclaims — and, many Christians say, divinely mediates — God’s spiritual cleansing and a new nature from above.
These ideas all converge in one conclusion: fallen human beings need a new nature if they are ever to see God’s kingdom. In the next sentences, Jesus plainly explains his own comment concerning water and Spirit. “That which is born of the flesh is flesh; and that which is born of the Spirit is spirit. Do not marvel that I said to you, ‘You [plural] must be born again'” (John 3:6-7). Eagle eggs hatch eaglets. Turtle eggs produce turtles. Human birth, even of chosen Jews or pious Pharisees, only produces fallen humans. But whoever is regenerated by God’s Spirit from above receives a new and spiritual nature — one that can share life with God and can live in his company forever.