Numbers 22:2

And Balak the son of Zippor saw all that Israel had done to
the Amorites.
] The word "Amorites" being particularly pointed, shows, as Aben Ezra observes, that Sihon and Og are both meant, and that there were not among the kings of the land of Canaan any so great as they; wherefore when Balak, who was the present king of Moab, saw what Israel had done to them, that they had conquered them, and seized upon their kingdoms: he reasoned within himself, and said, as Jarchi represents him, that if they could not stand before Israel, much less could he and his people; and the rather, since those kings Israel had subdued were too powerful for the king of Moab, and had taken part of his country from him, and yet Israel was too strong for them.