This was a significant step toward fulfilling God's promise to Abram in Genesis 15:5; namely, that his descendants would be like the number of stars in the heavens. The children of Israel multiplied rapidly numerically and filled the land of Goshen. Their numbers increased so dramatically that it was a serious concern to the Egyptians. Their worry is rooted in the fear that the Israelites might rise up and leave, and this would be devastating to the Egyptian way of life.
"Now there arose a new king over Egypt, who did not know Joseph. And he said to his people, 'Look, the people of the children of Israel are more and mightier than we; come, let us deal shrewdly with them, lest they multiply, and it happen, in the event of war, that they also join our enemies and fight against us, and so go up out of the land.' Therefore they set taskmasters over them to afflict them with their burdens. And they built for Pharaoh supply cities, Pithom and Raamses. But the more they afflicted them, the more they multiplied and grew. And they were in dread of the children of Israel. So the Egyptians made the children of Israel serve with rigor. And they made their lives bitter with hard bondage--in mortar, in brick, and in all manner of service in the field. All their service was with rigor" (Exo. 1:8-14).
The kindness Joseph had done for Egypt was a thing of the past, and the kindness reciprocated toward the Israelites by the Egyptian authorities was no more. The text does not explain the shrewd behavior of the Egyptians that led to the Israelites becoming an enslaved people. Likely it was a gradual process that the Israelites (as isolated strangers in the land) were powerless to roll back once they realized the terrible situation they were in. The Egyptians could have labored to build a strong relationship of cooperation with the Israelites but instead chose to subjugate them out of fear. The Israelites were burdened with hard, vigorous, manual labor. But, this mistreatment did not slow down the incredible "swarms" of Israelite babies! Clearly, God was blessing their fertility and Pharaoh was impotent to stop it.
"Then the king of Egypt spoke to the Hebrew midwives, of whom the name of one was Shiphrah and the name of the other was Puah; and he said, 'When you do the duties of a midwife for the Hebrew women, and see them on the birthstools, if it is a son, then you shall kill him; but if it is a daughter, then she shall live.' But the midwives feared God, and did not do as the king of Egypt commanded them, but saved the male children alive. So the king of Egypt called for the midwives and said to them, 'Why have you done this thing, and saved the male children alive?' And the midwives said to Pharaoh, 'Because the Hebrew women are not like the Egyptian women; for they are lively and give birth before the midwives come to them.' Therefore God dealt well with the midwives, and the people multiplied and grew very mighty. And so it was, because the midwives feared God, that He provided households for them. So Pharaoh commanded all his people, saying, 'Every son who is born you shall cast into the river, and every daughter you shall save alive'" (Exo. 1:15-22).
If they could not slow down the population growth via harsh slave labor, then a more direct approach would be employed. The newborn males (who could grow up to rebel against Egypt or lead the Israelites away) were to be murdered at birth. But, not everyone would go along with this population control tactic. Those who feared God refused to obey the king--and rightly so (cf. Acts 5:29). There is no reason to believe the midwives lied to Pharaoh regarding the "lively" Hebrew births, though they clearly had no interest in murdering these babies. God blessed these midwives accordingly. Finally, in desperation, Pharaoh commands all of the Egyptians to throw any Israelite baby boy into the Nile. This command could not have been implemented very long or it would have resulted in the eventual extermination of Israel. Pharaoh's tactics are powerless against God's will! This will become a central theme in this first half of this book.