Luke gives the reason plainly: Festus was "willing to do the Jews a pleasure" (Acts 25:9). He was new to his post, and Barnes says he was "desirous of securing their favor, as he had just entered on his administration." Barnes adds that this showed "rather a desire of popularity than an inclination to do justice." The move to Jerusalem was exactly what the Jewish leaders had asked for, since they planned to ambush Paul on the way (Acts 25:3). Yet Festus asked rather than ordered. Barnes notes that he still had "such a sense of justice and law as not to suffer the case to go out of his own hands": the trial would still be "before me."

Paul refused: "I stand at Caesar's judgment seat, where I ought to be judged: to the Jews have I done no wrong, as thou very well knowest" (Acts 25:10). He did not try to escape a just penalty: "if I be an offender... I refuse not to die." But if the charges were false, "no man may deliver me unto them. I appeal unto Caesar" (Acts 25:11). Festus conferred with his council and granted the appeal: "unto Caesar shalt thou go" (Acts 25:12).

Festus had replaced Felix, who had also left Paul bound because he was "willing to shew the Jews a pleasure" (Acts 24:27). Gill says Festus had "just entered upon his new government" and had met with civilities from the Jews at Jerusalem, and that going to Jerusalem was "what the Jews had requested of him."

Paul was a Roman citizen (Acts 22:25-28), and Barnes explains that under older Roman laws a citizen facing a beating or death could "appeal to the Roman people, and this appeal carried the cause to Rome"; later such appeals went to the emperor. By appealing to Caesar, Paul took his case out of the governor's hands and away from Jerusalem.

This question looked like a courtesy, but it carried danger. Behind it was a plot to kill Paul on the road (Acts 25:3). Paul refused it and used the legal rights God had placed in his hands. His appeal did not come from fear of death; he said plainly that if he had done wrong, "I refuse not to die" (Acts 25:11). He was refusing to be handed over to injustice.

God had already told Paul he must "bear witness also at Rome" (Acts 23:11). A governor trying to please the crowd ended up setting Paul's feet on the road to Rome. The pressure meant to bring Paul back to Jerusalem became the very means of carrying the gospel toward the center of the empire.