Paul had just said he was on trial for the very hope Israel's twelve tribes served God "day and night" to reach (Acts 26:7). That hope included the resurrection. So he turns and asks why anyone should find it unbelievable that God, of all beings, should raise the dead. Barnes points out that "you" is plural, so Paul was speaking to the whole assembly, not only Agrippa. He sees no evidence that Agrippa doubted the resurrection, but thinks Festus and those with him probably did. Gill takes the "you" as the heathens and Sadducees, for whom resurrection was an incredible doctrine, and says Paul may be thought to address either Festus and the chief captains or else King Agrippa, "who might be a Sadducee," with any Sadducees in court. The question puts the issue where it belongs: not on what seems possible to us, but on the power of God.

No one answers out loud. Paul answers the question himself as he goes on. He tells how he once fought "the name of Jesus of Nazareth" until the risen Jesus met him on the road to Damascus (Acts 26:9-15). He ends by saying the prophets and Moses foretold "that Christ should suffer, and that he should be the first that should rise from the dead" (Acts 26:22-23). At that point Festus breaks in "with a loud voice, Paul, thou art beside thyself; much learning doth make thee mad" (Acts 26:24).

The word "incredible" translates apiston, unbelievable or not to be trusted. "Be thought" is krinetai, literally "is it judged." Paul is asking why they have judged the resurrection to be something beyond belief.

The Jews were divided on this. "The Sadducees say that there is no resurrection, neither angel, nor spirit: but the Pharisees confess both" (Acts 23:8). Paul had been raised a Pharisee (Acts 26:5). Many Gentiles also scorned the idea; Gill notes it was laughed at by the philosophers at Athens when Paul preached there (Acts 17:18, 32). Barnes suggests that the force of the question is better seen by pausing after "why": "What! is it to be thought a thing incredible?"

This question goes to the heart of who God is. If God made all things and gives life, raising the dead is not beyond Him. Matthew Henry sums it up: "If it be above the power of nature, yet it is not above the power of the God of nature."

Paul did not argue in the abstract. He went straight from this question to his own story: he had met Jesus alive after His death (Acts 26:13-15). The resurrection was not just a doctrine he defended; it was the hope of Israel fulfilled in a Person he had seen. That is why he could say that Christ "should be the first that should rise from the dead," bringing light "unto the people, and to the Gentiles" (Acts 26:23).