John Chrysostom

Prophets had power either to speak or to refrain from speaking. They were not bound by necessity but were honored with a privilege. For this reason Jonah fled, for this reason Ezekiel delayed and for this reason Jeremiah excused himself. And God drives them not only by compulsion but also by advising, exhorting, threatening. He does not darken their mind, because to cause distraction, madness and great darkness is the proper work of a demon. It is God's work to illuminate and with consideration to teach what is necessary.