Albert Barnes Commentary Numbers 23:9

"For from the top of the rocks I see him, And from the hills I behold him: lo, it is a people that dwelleth alone, And shall not be reckoned among the nations." — Numbers 23:9 (ASV)

For from the top of the rocks ... - The word “for” indicates the constraint under which Balaam found himself. He had been met by God in his own way; from the cliff he had watched for the expected augury; and by the light of this, he interprets, according to the rules of his art, the destiny of Israel.

Dwell alone - that is, apart from others, undisturbed by their tumults, and therefore in safety and true security. Compare this same idea with Jeremiah 49:31 and Micah 7:14.

This tranquility was realized by the Israelites as long as they clung to God as their shelter and protection. But the inward “dwelling alone” was the indispensable condition of the outward “dwelling alone,” and as soon as the influence of the pagan world affected Israel internally, the external power of paganism also prevailed. Balaam himself, when he eventually counseled tempting the people into sin, acted upon the knowledge that God’s blessing and Israel’s prosperity depended essentially on faithfulness to God.