What does Exodus 1:20 mean?

Verses 20 and 21 note several positive developments in the midst of Pharaoh's persecutions. First, God responds to the dangerous choice made by the midwives, in defying Pharaoh's evil order. They had protected the young lives of Israel's sons, risking their own lives in the process. God blessed them as a result. This likely included Shiphrah and Puah, as well as other Jewish midwives who protected young lives. Second, "the people multiplied." Despite Pharaoh's repeated efforts to limit population growth, the Jews continue to grow in number.

Third, the result of these events was a nation of Israel that continued to threaten the Egyptians due to their size. Pharaoh would soon choose even more drastic measures to kill newborn Jewish males (Exodus 1:22). This command is given to all of Egypt, specifically to throw Hebrew boys into the Nile river.

Ironically, in the context of this wicked command, God allowed a baby boy to be literally "cast into" the Nile, yet protected and raised up within Pharaoh's own household, becoming the rescuer of the people of Israel (Exodus 2:1–10). This child would be known by his name: Moses, meaning "draw out," based on Pharaoh's daughter drawing him out of the water.