Acts 25:14 - Ellicott's Commentary On The Whole Bible

Festus declared Paul’s cause unto the king. — The matter seems to have come in, as it were, in the course of conversation. Festus probably thought that Agrippa, who knew all about the Jews and their religion, could throw some light on the peculiar position of his prisoner, who, though a Jew, and professing the utmost reverence for the Law and the Temple, was yet accused and denounced by his compatriots.