There wasn't 3 million Jews.
They numbered in the thousands at the most.
(Gen 47:1 KJV)
Then Joseph came and told Pharaoh, and said, My father [ISRAEL] and my brethren, and their flocks, and their herds, and all that they have, are come out of the land of Canaan; and, behold, they are in the land of Goshen.
(Gen 47:3 KJV)
And Pharaoh said unto his brethren, What is your occupation? And they said unto Pharaoh, Thy servants are shepherds, both we, and also our fathers.
(Gen 47:5 KJV)
And Pharaoh spake unto Joseph, saying, Thy father [ISRAEL] and thy brethren are come unto thee:
(Gen 47:6 KJV)
The land of Egypt is before thee; in the best of the land make thy father and brethren to dwell; in the land of Goshen let them dwell: and if thou knowest any men of activity among them, then make them rulers over my cattle.
Three million shepherds-- I think not

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