Deuteronomy 8:2, 16

And you shall remember [always] all the ways which the LORD your God has led you these forty years in the wilderness, so that He might humble you and test you, to know what was in your heart (mind), whether you would keep His commandments or not.

He fed you manna in the wilderness, [a substance] which your fathers did not know, so that He might humble you [by dependence on Him] and that He might test you, to do good [things] for you at the end.