What does 2 Kings 8:13 mean?

Hazael said, 'How could someone like me ever do something so terrible?' Elisha answered, 'God has shown me that you’re going to be king of Syria.' 2 Kings 8:13 - Modern Text Bible

(Hazael is shocked at the idea he could commit the violent acts Elisha describes, but Elisha tells him plainly that he will become king and do these things.)