What does John 11:49 mean?

Those familiar with the Old Testament's explanation of the High Priesthood will notice that Caiaphas is described as holding his title "that year." High priests were meant to be appointed for life (Numbers 35:25). While the Roman Empire was willing to let conquered territories self-govern, to an extent, they didn't like the idea of locals holding too much power. So, they installed their own appointed high priests as they saw fit. Caiaphas is one of these, a Sadducee, who does not share the Pharisees unique interpretations of Judaism. What he does share is their concern—or at least, their claims—that Jesus represents the kind of threat Rome might respond to with violence. Just as much of a worry is that Jesus' disruption might lead to the Romans upsetting their positions of power (John 11:48).

In drama or literature, Caiaphas is often portrayed as arrogant, cruel, and spiteful. Scripture doesn't say much about his personality. However, in this case, he's speaking to—and insulting—an entire council of supposedly educated men. As the nominal leader of the group that deliberately perverts justice so that Jesus will be killed, he's subject to such criticism. Little of what's recorded from Caiaphas in the New Testament softens that patronizing, pompous reputation.