Why hast. — Rather, What is this that thou hast done? The question expresses horror, not curiosity.
For the men knew that. — Jonah’s answer in Jonah 1:9 is evidently intended only as an abbreviation of what he actually replied.
Related Commentaries of Jonah 1:10
Jonah 1:10
10 Then were the men exceedinglyd afraid, and said unto him, Why hast thou done this? For the men knew that he fled from the presence of the LORD, because he had told them.