Pharaoh dreams two troubling dreams, one about seven gaunt cows that swallow seven fat cows, and one about seven thin and blighted stalks of grain that swallow seven plump ones. Joseph is summoned to interpret the dreams only after Pharaoh’s wise men unsuccessfully attempt to interpret the dreams, and Pharaoh’s mood has turned dark. Joseph’s interpretation is accepted.

“He sent and called for all the magicians of Egypt, and all its wise men; Pharaoh related his dream to them, but no one could interpret them for Pharaoh” (Genesis 41:8). The wise men would suggest interpretations, but he would not listen to what they said. They suggested: The seven good cows indicate that you will beget seven daughters, and the seven unsightly cows indicate that you will bury seven daughters. Likewise they said: The seven good stalks indicate that you will conquer seven kingdoms, and the seven blighted stalks indicate that seven principalities will rebel against you…. And why did they give Pharaoh so many incorrect interpretations? So that Joseph would ultimately come and acquire greatness. The Holy One, blessed be He, said: Were Joseph to come first and interpret the dream, that would not lead to his being praised. The astronomers could come and say to Pharaoh: Had you asked us, we would already have interpreted it for you. Rather, God waited for them until they exhausted and depressed Pharaoh’s spirit; thereafter Joseph came and restored it. (Bereshit Rabba 89)