5 All those who were descendants [1] of Jacob were seventy [2] persons (for Joseph was in Egypt already). 6 And Joseph died, all his brothers, and all that generation. 7 But the children of Israel were fruitful and increased abundantly, multiplied and grew exceedingly mighty; and the land was filled with them.
Matthew Henry's Commentary on Exodus 1:5-7
Commentary on Exodus 1:1-7
(Read Exodus 1:1-7)
During more than 200 years, while Abraham, Isaac, and Jacob lived at liberty, the Hebrews increased slowly; only about seventy persons went down into Egypt. There, in about the same number of years, though under cruel bondage, they became a large nation. This wonderful increase was according to the promise long before made unto the fathers. Though the performance of God's promises is sometimes slow, it is always sure.