Our Lord and Nicodemus continue their conversation, or we might call it the instruction of Nicodemus. How can one be “born of water and Spirit” (John 3:5)? “How can this happen?” asks Nicodemus (John 3:9). Of course, the answer is baptism into the “Son of Man,” for “everyone who believes in him may have eternal life” (John 3:15). Faith opens the eyes, the ears, the mind and the heart to comprehend what is the object of belief. Faith is a dynamic reality, a gift from God, that allows the believer to grasp the truth of the Son of Man (cf. John 3:11).
Where is the Son of Man manifested? Commenting on this encounter between our Lord and Nicodemus, St. John Chrysostom writes, “Having made mention of the gift of baptism, He proceeds to the source of it, i.e. the cross” (Homily XXVII, 1). “[J]ust as Moses lifted up the serpent in the desert, so must the Son of Man be lifted up, so that everyone who believes in him may have eternal life” (John 3:14-15). Our Lord is referring here to a fascinating episode in the Book of Numbers (Numbers 21:4-9), where God sent saraph serpents to attack the Israelites in punishment for their complaining. Moses beseeches God for deliverance and pardon. God responds favorably by commanding Moses to fashion a serpent and mount it on a pole, so that anyone bitten who looks upon it may be cured. “[S]o must the Son of Man be lifted up” (John 3:14). Our Lord is lifted up on the cross at Calvary to be manifested as much more than a cure, indeed the very source of eternal life (John 3:15), the source of sacramental life, the Sacrament of Salvation. Recall the blood and water that flow from Christ’s pierced side at Calvary (John 19:34). St. Augustine comments on this passage: “[W]hereby was opened the gate of life, from whence the sacraments of the Church flowed, without which we cannot enter into that Life which is the true life” (Tractate 120, 2).