John Calvin on Genesis 41:35-37

35. Under the hand of Pharaoh. Whereas prosperity so intoxicates men, that the greater part make no provision for themselves against the future, but absorb the present abundance by intemperance; Joseph advises the king to take care that the country may have its produce laid up in store. Besides, the common people would also form themselves to habits of frugality, when they understood that this great quantity of corn was not collected in vain by the king, but that a remedy was hereby sought for some unwonted calamity. In short, because luxury generally prevails in prosperity, and wastes the blessings of God, the bridle of authority was necessary. This is the reason why Joseph directed that garners should be established under the power of the king, and that corn should be gathered into them. He concludes at length, that the dream was useful, although at first sight, it would seem sad and inauspicious: because, immediately after the wound had been shown, the means of cure were suggested.