Midrash su Deuteronomio 32:15

(Devarim 1:1) "These are the words which Moses spoke, etc.": Now did Moses prophesy only these? Did he not write the entire Torah, viz. (Ibid. 31:9) "And Moses wrote this Torah"? What, then, is the intent of "These are the words"? We are hereby taught that they were words of rebuke, viz. (Ibid. 32:15) "And Yeshurun grew fat and it kicked, etc."

(Devarim 32:15) "And Yeshurun grew fat and it kicked": Satiety breeds rebellion. And thus we find with the men of the generation of the flood — that they rebelled against the L-rd only from (a superabundance of) food and drink and tranquility. What is written of them? (Iyyov 21:9) "Their houses are at peace, without fear. The rod of G-d is not upon them." (see #43 above). And thus we find with the men of the generation of the desert, that they rebelled against the L-rd only from (a superabundance of) food and drink, viz. (Shemoth 32:6) "and the people sat down to eat and drink." What follows? (Ibid. 8) "They have turned quickly from the way that I have commanded them, etc." The Holy One Blessed be He said to Moses: When Israel enters the land, they are destined to rebel from (a superabundance of) food and drink and tranquility, (viz. Devarim 31:20) "For I shall bring them to the land that I have sworn to their fathers, flowing milk and honey, and they shall eat and be sated and grow fat, and they shall turn to other gods, etc." Moses said to Israel: When you enter the land, see to it that you do not rebel against the L-rd through eating, drinking, and tranquility, viz. (Ibid. 8:12-13) "Lest you eat and be sated … and your herds and your flocks increase, etc." What follows? (Ibid. 14) "and your heart be lifted and you forget the L-rd your G-d."