Then the high priest - The high priest at this time was Ismael, the son of Fabi. He had been promoted to that office by Agrippa (Josephus, Antiq., book 20, chapter 8, section 8). It is probable, however, that the person here intended was Ananias, who had been high priest, and who would retain the name. See the notes on Acts 23:2. Some mss. read "high priests" here in the plural number, and this reading is approved by Mill and Griesbach. There is, however, no improbability in supposing that the high priest Ismael might have been also as much enraged against Paul as the others.
Informed him against Paul - Informed him of the accusation against him, and doubtless endeavored to prejudice the mind of Festus against him. They thus showed their unrelenting disposition. It might have been supposed that after two years this unjust prosecution would be abandoned and forgotten. But malice does not thus forget its object, and the spirit of persecution is not thus satisfied. It is evident that there was here every probability that injustice would be done to Paul, and that the mind of Festus would be biased against him. He was a stranger to Paul, and to the embittered feelings of the Jewish character. He would wish to conciliate their favor upon entering into the duties of his office. A strong representation, therefore, made by the chief men of the nation, would be likely to prejudice him violently against Paul, and to unfit him for the exercise of impartial justice.

The high priest - informed him against Paul - They supposed that as Felix, to please them, on the resignation of his government, had left Paul bound, so Festus, on the assumption of it, would, to please them, deliver him into their hand; but, as they wished this to be done under the color of justice, they exhibited a number of charges against Paul, which they hoped would appear to Festus a sufficient reason why a new trial should be granted; and he be sent to Jerusalem to take this trial. Their motive is mentioned in the succeeding verse.

Then the high priest,.... Ananias, as in Acts 23:2 the Alexandrian copy, the Vulgate Latin version, and all the Oriental versions, read, "the chief priests", the whole college of the priests:
and the chief of the Jews; their rulers and elders, the members of the Jewish sanhedrim;
informed him against Paul; they took the first opportunity of waiting upon him, when he was come to Jerusalem; hoping it might be a favourable one to them, since he was just entering upon his government, and might be willing to gratify the chief of the nation, and gain their affection and esteem, and since as yet he was not acquainted with their wicked dispositions and artifices; and brought a bill of information against Paul, and gave a large account of him, what a wicked man he was, and what evils he had committed; they laid many things to his charge, and very heavily accused him, and endeavoured to prepossess the governor, and prejudice him against him:
and besought him; that he would grant them the following request.

Then the high priest--a successor of him before whom Paul had appeared (Acts 23:2).
and the chief of the Jews--and "the whole multitude of the Jews" (Acts 25:24) clamorously.
informed him against Paul . . .

Then the high priest and the chief of the Jews appeared against Paul - In so long a time their rage was not cooled. So much louder a call had Paul to the Gentiles.