Jamieson, Fausset and Brown on Numbers 23:9

9. from the top--literally, "a bare place" on the rocks, to which Balak had taken him, for it was deemed necessary to see the people who were to be devoted to destruction. But that commanding prospect could contribute nothing to the accomplishment of the king's object, for the destiny of Israel was to be a distinct, peculiar people, separated from the rest of the nations in government, religion, customs, and divine protection (De 33:28). So that although I might be able to gratify your wishes against other people, I can do nothing against them (Ex 19:5; Le 20:24).