Jesus describes His death as His glorification/exaltation. Elevated on the cross, it’s as if Jesus had taken the throne to pass judgment on this world and to cast out the ruler of this world (John 12:31).
John’s narrative prepares the way for this declaration. In chapter 11, Jesus raises Lazarus from the dead, in a preview of Jesus’ own resurrection, and at the beginning of chapter 12, Lazarus is sitting among those who share a meal in Bethany, as Jesus will later eat with His disciples after His resurrection.
After resurrection comes ascension, and John offers a preview of ascension in the event of Palm Sunday: The crowds that sing Hosanna anticipate the angelic hosts that will welcome the Lamb into heaven.
The Pharisees worry that all the world has gone after Jesus (12:19), and it’s not simply the Jews: Greeks are looking for Jesus too (12:20).
Death, resurrection, ascension, proclamation to the nations: All this is foreshadowed during Passion week.
And this is the context in which Jesus speaks of the judgment of this world. This fits the sequence: After the nations are gathered, there will be a judgment. But this sequence isn’t fulfilled in John’s gospel. To see the fulfillment of what John foreshadows, we have to read John and Revelation together. John records no ascension, but Revelation does (Revelation 4-5). John doesn’t speak about the destruction in the temple in His gospel, as the synoptics do (fittingly, during holy week!) but John elaborates the future of the harlot city in Revelation.
Now is the judgment of this world: Jesus refers to the cross. But that judgment is complete when Jesus finishes His return to the Father, takes His seat, and pours out the wrath of the Lamb.
(Much of this was inspired by a Palm Sunday sermon by Pastor Rich Lusk, of Trinity Presbyterian Church, Birmingham.)