The king’s response is a contesting of Jephthah’s claim. He argues that the land east of the Jordan, from the Arnon River in the south to the Jabbok River in the north, belonged to him and had been illegally seized when Israel came from Egypt. So he wants Israel to give it back peaceably.
13 And the king of the Ammonites answered the messengers of Jephthah, “Because Israel on coming up from Egypt took away my land, from the Arnon to the Jabbok and to the Jordan; now therefore restore it peaceably.”