He restored the border of Israel from the entrance to Hamas to the sea of Arava according to the word of Hashem, the G-d of Israel, that He spoke through the hand of His servant Jonah, the son of Amittai, the prophet, who was from Gas-Hachefer.
Did you know that Yonah (Jonah) was in the Book of Kings? Well, here he is! But whatever prophecy is alluded to here is unrecorded - and problematic, since we have a tradition that G-d only spoke with Yonah twice and this would make a third time! The Radak cites a discussion on this matter from Talmud Yevamos 98a. One explanation is that G-d only spoke with Yonah twice about Nineveh but this is a different matter. The other explanation is that Yonah did not have a prophecy here; what it means is that the Jews repented and turned themselves around at this time just like the people of Nineveh did in response to Yonah’s prophecy.