Ex 1-18 narrate the wonderful story of God's deliverance of His people from Egypt. They cover around 80 years, being the first 80 years of Moses' life. Hundreds of thousands of Israelites had never lived in freedom, and God brought them into freedom. Later, this is seen as the standard of God's power; see Mic 7.15.
v1-5: The link back to Genesis, as 70 people in one family were settled into Egypt (see Gen 46.26-27). The family was initially respected by the Egyptians, and given the best part of the land (Gen 45.18). It is from this family that a nation of hundreds of thousands grew.
v6-7: At first, the seventy were no threat to the Egyptians, but the combination of a new king of Egypt who did not know of Joseph (v8), and the rapidly growing people (v7,9), changed the environment into one of real antagonism.
v8: The new king perhaps refers to a new dynasty in Egypt. He knew nothing of Joseph's rule in the years of famine, which preserved the nation.
v9: The Israelites, allegedly had grown more numerous than the Egyptians. We don't know if this was true, or whether the new king simply hated them. There is a suggestion that the previous dynasty was of Semitic origin, and the new of Hamitic.
v10: The fear was that, if war arose, the Israelites would ally themselves with Egypt's enemies. The answer was to "deal shrewdly" with the Israelites, so that they would not grow further. The Egyptians, in setting themselves against the Israelites, actually opposed God. Such a course of action was seen, in due course, to be the peak of folly.
v11-14: The plan was hatched, to use the Israelites as slaves. Two great cities were built. But the plan backfired, as the Israelites grew even more numerous. The Egyptians grew to hate them even more.
The Israelites were treated "ruthlessly" (or "with rigour"), which implies severity and cruelty. In Lev 25.43,46 the Israelites were forbidden from treating their own slaves this way; we may suffer such treatment at the hands of men, but we must not treat others this way.
v15-16: The further plan, to kill the new born male children. Pharaoh told the two Israelite midwives, Shiphrah and Puah to do this. They were thus asked to betray their own people. To kill males not only prevents future generations, it also destroys leadership and authority. Pharaoh, like Herod (Matt 2.16), stoops at nothing to ensure his schemes are fulfilled.
v17-19: The midwives, however, refused to obey Pharaoh's command. Instead, they feared God, and let the boys live. They then defended their actions. Whether they told the exact truth is not the issue; they remained loyal to their own people. Further, to have obeyed Pharaoh would have made them guilty of murder.
Submission is a matter of attitude, but obedience is a matter of conduct. The midwives showed submission to Pharaoh, but rendered obedience to God.
v20-21: God blessed the midwives, rewarding them for their faithfulness.
v22: The fresh command, that the male children are thrown into the river Nile. The Egyptian people were now involved, and presumably carried out the command, since, in chapter 2, Moses' mother tried to hide her baby from the Egyptians. It is into this environment that Moses is born.