Deuteronomy 8:3-5

Amplified Bible

³ He humbled you and allowed you to be hungry and fed you with manna, [a substance] which you did not know, nor did your fathers know, so that He might make you understand [by personal experience] that man does not live by bread alone, but man lives by every word that proceeds out of the mouth of the Lord. ⁴ Your clothing did not wear out on you, nor did your feet swell these forty years. ⁵ Therefore, know in your heart (be fully cognizant) that the Lord your God disciplines and instructs you just as a man disciplines and instructs his son.