Adam Clarke's Commentary on the Bible

Verse 18 (Deuteronomy 8:18)

God - giveth thee power to get wealth - Who among the rich and wealthy believes this saying? Who gives wisdom, understanding, skill, bodily strength, and health? Is it not God? And without these, how can wealth be acquired? Whose is providence? Who gives fertility to the earth? And who brings every proper purpose to a right issue? Is it not God? And without these also can wealth be acquired? No. Then the proposition in the text is self-evident: it is God that giveth power to get wealth, and to God the wealthy man must account for the manner in which he has expended the riches which God hath given him.

- Adam Clarke's Commentary on the Bible