Hear diligently my speech - That which I have made; that is, the declaration which I have made of my innocence. He refers to his solemn declaration, Job 13:15-16 that he had unwavering confidence in God, and that even should God slay him he would put confidence in him. This solemn appeal he wished them to attend to as one of the utmost importance.
Related Commentaries of Job 13:17
Job 13:17
17 Hear diligently my speech, and my declaration with your ears.