English Standard Version
And as he was saying these things in his defense, Festus said with a loud voice, "Paul, you are out of your mind; your great learning is driving you out of your mind."New International Version
At this point Festus interrupted Paul's defense. "You are out of your mind, Paul!" he shouted. "Your great learning is driving you insane."Catholic Public Domain Version
While he was speaking these things and presenting his defense, Festus said with a loud voice: "Paul, you are insane! Too much studying has turned you to insanity.