Exodus 1:7

The children of Israel were fruitful. — A great multiplication is evidently intended. Egypt was a particularly healthy country, and both men and animals were abnormally prolific there. Grain was so plentiful that want, which is the ordinary check on population, was almost unknown. The Egyptian kings for many years would look favourably on the growth of the Hebrew people, which strengthened their eastern frontier, the quarter on which they were most open to attack. God’s blessing was, moreover, upon the people, which he had promised to make “as the stars of the heaven, and as the sand which is upon the sea-shore, for multitude” (see Genesis 22:17). On the actual extent of the multiplication and the time that it occupied, see the comment on Exodus 12:37.

The land — i.e., where they dwelt — Goshen (Genesis 47:4) — which seems to have been the more eastern portion of the Delta.