Why does the senator say that Othello must leave that same night?​

The Duke tells Othello that he can make what arrangements he likes. The important thing is that he must leave this very night because "the' affair calls [for] haste"

the affair calls [for] haste

Explanation:

the answer is emerged from.

orpheus descended to hades, the world of the death to rescue eurydice. no mortal had ever done this before him, he survived because he was protected by the gods. the word "underworld" gives us a clue, he emerged from it like a whale emerges form sea for exemple.