Genesis 47:20

It seems to me that censure of the Egyptians is contained also in this statement. For you would not easily find it written of the Hebrews that "the famine prevailed over them." For although it is written that "the famine prevailed over the land," nevertheless it is not written that famine prevailed over Jacob or his sons, as it is said of the Egyptians, that "the famine prevailed over them." For although famine should come also to the just, nevertheless it does not prevail over them. For this reason the just glory in famine, as Paul is found to rejoice cheerfully in sufferings of this kind when he says, "In hunger and thirst, in cold and nakedness." What therefore is an exercise of virtue for the just is a penalty of sin for the unjust.For it is written also in the times of Abraham that "there came a famine in the country, and Abraham went down to Egypt to dwell there, since the famine prevailed in the land." And certainly if, as some think, the text of the divine Scripture was composed carelessly and awkwardly, it could have said that Abraham went down to Egypt to dwell there because the famine prevailed over him. But observe how great a distinction the divine word uses, how great a caution it employs. When it speaks of the saints it says the famine had prevailed "over the land"; when it speaks of the unjust it says they were held by the famine. Famine therefore prevailed over neither Abraham nor Jacob nor their sons.

Since you see, therefore, that an observation of this kind is preserved correctly in almost all the texts of holy Scripture, interpret these words in their figurative and allegorical meaning, which we are taught by the words of the prophets themselves no less.

And Joseph bought all the land of Egypt for Pharaoh,....