It's my understanding that Jesus’s phrase “born again” in John 3 refers to the new supernatural life God gives the soul — a life that does not come from human birth (“born of flesh”) but from the Spirit (“born of Spirit”). In the dialogue, Jesus contrasts what human nature can generate with what only God can generate. Flesh produces merely natural life; Spirit produces divine life.
When Jesus speaks of “water and Spirit,” He is describing the two inseparable aspects of this rebirth:
- “Water” corresponds to the purification and renunciation of the old life — the cleansing that prepares the soul for God.
- “Spirit” is the infusion of divine life that enables the soul to live in a new way, with capacities it did not possess before.
John 3 also explains how one knows this rebirth has occurred: not by feelings, but by the effects Jesus describes — the ability to perceive (“see”) and enter the kingdom of God, a new interior orientation toward truth, and a life shaped by the Spirit rather than the flesh. Rebirth gives the soul the capacity to recognize and respond to the movements of the Spirit. As Jesus teaches with the image of the wind, the Spirit comes freely and cannot be controlled, but His presence is known by His effects; and only the soul that is alert, like a sailor who unfurls the sails at the right moment, can follow His call. This is why Nicodemus cannot understand rebirth (“How can these things be?”): without faith in the Incarnate Word, he cannot perceive the Spirit’s action, just as Jesus says that one must first believe in the Son to recognize the Spirit’s voice. The Spirit’s work is known by its fruits, and the reborn soul knows the voice of the Spirit of whom it was born.
The chapter’s later focus on baptism (“Jesus and His disciples went into the Judean countryside, and He baptized”) shows the sacramental context in which this rebirth is ordinarily given. Baptism is the visible, ecclesial means by which the purification (“water”) and vivification (“Spirit”) Jesus describes are conferred. But the essence of being “born again” is the interior reality itself — the soul’s rebirth through God, the creation of a new life that flesh cannot produce.