This is direct quotation. It can also be stated as an indirect quotation: “Then Elijah told King Ahab to return immediately to his home, because the rain was coming.” (See: [[rc://en/ta/man/translate/figs-quotations]])
The connecting word **Then** introduces a sequential clause. The prophets of Baal were killed, and then Elijah warned Ahab. (See: [[rc://en/ta/man/translate/grammar-connect-time-sequential]])