Albert Barnes on Acts 25:22

Then Agrippa said, etc. Agrippa doubtless had heard much of the fame of Jesus, and of the new sect of Christians; and probably he was induced by mere curiosity to hear what Paul could say in explanation and defence of the doctrine of Christianity. This wish of Agrippa gave occasion to the noblest defence which was ever made before any tribunal, and to as splendid eloquence as can be found anywhere in any language. See Acts 26.