Thank you for the question on the population of the Israelites who left Egypt, “How did the population of the ancient Israelites go from Jacob and his 12 sons and their families to over a million people by the time God freed them from Egypt?
The subject of the growth of the population of the Israelites is a continuing debate among Bible scholars and skeptics of the Bible.
The Scripture states that 70 sons of Jacob went down into Egypt. Genesis 46 says this, ” 26 All those who went to Egypt with Jacob—those who were his direct descendants, not counting his sons’ wives—numbered sixty-six persons. 27 With the two sons who had been born to Joseph in Egypt, the members of Jacob’s family, which went to Egypt, were seventy in all” (NIV).
If I may add four observations on the subject as others have commented and given their calculations.
A. The number of sons, not including their wives were seventy in all.
In reality if one includes their wives, the number would be much greater. How many wives did Jacob’s had before they went into Egypt and after they entered Egypt is unknown. It is faulty thinking that while in Egypt that Jacob’s children did not marry other women and had more children while in Egypt.
B. The number of Jacob’s grandsons appears not to be list in the 70.
For example, the sons of Reuben: Hanoch, Palin, Hezon and Carmi (Gen. 46:9). Were any of these sons married and had children? It would seem likely that at least some of Jacob’s children married and had other children. They are not listed except for the direct descendent and not their grandchildren. The Scripture is silent on when Jacob’s grandchildren were born to him.
It is note that Joseph was 17 when he was in Egypt and 30 years old when he became prime minster of Egypt (Gen. 41:46). If Joseph was 30 when he became prime minister, this means that there was more than enough time for Jacob’s 11 sons to marry and had children. One one remember that Joseph was born years apart from his oldest brother. Thus the 70 only list the first generation born to Jacob’s children and NOT their grandchildren.
C. The servants of Jacob are not mentioned in the entry into Egypt.
Jacob was not a poor shepherd. He was a wealthy man with abundance of animals and servants who tended his flocks. Jacob told his servants to present the gifts to Esau. Thus the people within Jacob’s household did not include servants. The number of servants that Jacob had is unknown but it may be assumed that he had a good number of servants and maids.
Jacob’s male servants were circumcised and became part of the Israelites. They were not his direct descendants but they were part of his household. Did any of the Jacob’s children or grandchildren married any of the servants? It would seem likely as Jacob married Rachel and Leah’s servants.
D. The increased wealth and status of the Jacob’s children under Joseph.
It is likely that under Joseph’s position that Jacob and his children were privilege and more servants were part of their family. Joseph lived to 110 years old (Gen. 50:22). This means that he ruled for 80 years or so until that Pharaoh died and perhaps under the next Pharaoh. In those years, it is likely that some of the Egyptians or other people group became Jews. Perhaps even some of the Egyptians sold themselves to the Jews for lack of food during the famine.
Thus by the time of the Exodus, including the direct descendants and servants who became part of the Jewish family, there was a considerable number of people. The text states that over 600,000 men left Egypt. I would imagine that this would include both direct descendants and household servants who over time became part of the family of the various tribes.
The descendants who entered Egypt with Jacob were 70 but it does not include grandchildren and servants nor does it include other people who married into the Jewish families and their servants while they were in Egypt. With the famine, the Jews were in a position to accumulate more servants in their household and married whomever they wanted.
SUMMARY: Could there be more than a million people who left Egypt? It is likely in my viewpoint with the grandchildren of Jacob, their servants, and their status in Egypt under Joseph that the Israelites became a large people group living in Egypt with wealth and property. They had 80 years of it under Joseph.
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