John 3:14

In another sense Jesus would rise up to heaven. The Ascension is not in view here. Jesus’ enemies lifting Him up toward heaven as Moses lifted the serpent on the pole toward heaven is in view (cf. Numbers 21:4-9). In the wilderness God promised the Israelites that whoever looked on the bronze serpent would receive physical life and not die.

This is Jesus’ earliest recorded prediction of His death. It is an allusion to death by crucifixion (cf. John 8:28; John 12:32; John 12:34). Wherever the Greek word hypsoo ("lifted up") occurs in John’s Gospel, and it only occurs in these four verses, it combines the ideas of crucifixion and exaltation (cf. Isaiah 52:13 to Isaiah 53:12). [Note: Carson, p. 201.] The Synoptic evangelists viewed Jesus’ exaltation as separate from His crucifixion, but John thought of the crucifixion as the beginning of His exaltation.

God had graciously provided continuing physical life to the persistently sinning Israelites. It should not, therefore, have been hard for Nicodemus to believe that He would graciously provide new spiritual life for sinful humanity.

John 3:13 pictures Jesus as the revealer of God who came down from heaven. John 3:14 pictures Him as the suffering exalted Savior. It was in His suffering that Jesus revealed God most clearly. These themes cluster around the title "Son of Man" in the fourth Gospel.