A.T. Robertson Commentary Acts 25:6

"And when he had tarried among them not more than eight or ten days, he went down unto Caesarea; and on the morrow he sat on the judgment-seat, and commanded Paul to be brought." — Acts 25:6 (ASV)

On the morrow (τη επαυριον). Locative case of the article with ημερα understood (επαυριον, adverb, tomorrow). Festus lost no time for the chief men had come down with him.

Sat on the judgment seat (καθισας επ του βηματος). A legal formality to give weight to the decision. Ingressive aorist active participle. For this use of βημα for judgment seat see on Mt. 27:19; John 19:13; Acts 12:21; 18:12; 25:10,17. Same phrase repeated in 25:17.

To be brought (αχθηνα). First aorist passive infinitive of αγω after εκελευσεν (commanded). Same words repeated in 25:17 by Festus.