Then the LORD said unto Moses, Now shalt thou see what I will do to Pharaoh: for with a strong hand shall he let them go, and with a strong hand shall he drive them out of his land.
With a strong hand — That is, being forced to it by a strong hand, he shall let them go.
 And God spake unto Moses, and said unto him, I am the LORD:
l am Jehovah — The same with I am that I am, the fountain of being and blessedness, and infinite perfection. The patriarchs knew this name, but they did not know him in this matter by that which this name signifies. God would now be known by his name Jehovah, that is, 1. A God performing what he had promised, and so giving being to his promises. 2. A God perfecting what he had begun, and finishing his own work. In the history of the creation God is never called Jehovah, till the heavens and the earth were finished, Revelation 22:13, in the mean time they shall find him for their strength and support, El-shaddai, a God All-sufficient, a God that is enough.
 And I have also heard the groaning of the children of Israel, whom the Egyptians keep in bondage; and I have remembered my covenant.
I have heard the groaning of the children of Israel — He means their groaning on occasion of the late hardships put upon them. God takes notice of the increase of his people's calamities, and observes how their enemies grow upon them.
 Wherefore say unto the children of Israel, I am the LORD, and I will bring you out from under the burdens of the Egyptians, and I will rid you out of their bondage, and I will redeem you with a stretched out arm, and with great judgments:
I will bring you out: I will rid you: I will redeem you: I will bring you into the land of Canaan; and, I will give it you - Let man take the shame of his unbelief which needs such repetitions, and let God have the glory of his condescending grace which gives us such repeated assurances.
With a stretched out arm — With almighty power: A metaphor taken from a man that stretches out his arm, to put forth all his strength.
 And I will take you to me for a people, and I will be to you a God: and ye shall know that I am the LORD your God, which bringeth you out from under the burdens of the Egyptians.
I will take you to me for a people — A peculiar people, and I will be to you a God - And more than this we need not ask, we cannot have, to make us happy.
 And I will bring you in unto the land, concerning the which I did swear to give it to Abraham, to Isaac, and to Jacob; and I will give it you for an heritage: I am the LORD.
I am the Lord — And therefore have power to dispose of lands and kingdoms as I please.
 And Moses spake so unto the children of Israel: but they hearkened not unto Moses for anguish of spirit, and for cruel bondage.
But they hearkened not to Moses for anguish of spirit — That is, They were so taken up with their troubles that they did not heed him.
 Go in, speak unto Pharaoh king of Egypt, that he let the children of Israel go out of his land.
That he let the children of Israel go — God repeats his precepts, before he begins his punishments. Those that have oft been called in vain to leave their sins, yet must be called again, and again.
 And Moses spake before the LORD, saying, Behold, the children of Israel have not hearkened unto me; how then shall Pharaoh hear me, who am of uncircumcised lips?
Behold, the children of Israel have not hearkened to me; they gave no heed to what I have said, how then shall Pharaoh hear me? - If the anguish of their spirit makes them deaf to that which would compose and comfort them, much more will his pride and insolence, make him deaf to that which will but exasperate him.
Who am of uncircumcised lips — He was conscious to himself that he had not the gift of utterance.
 And the LORD spake unto Moses and unto Aaron, and gave them a charge unto the children of Israel, and unto Pharaoh king of Egypt, to bring the children of Israel out of the land of Egypt.
The Lord gave them a charge, both to the children of Israel, and to Pharaoh — God's authority is sufficient to answer all objections, and binds us to obedience without murmuring or disputing.
 These be the heads of their fathers' houses: The sons of Reuben the firstborn of Israel; Hanoch, and Pallu, Hezron, and Carmi: these be the families of Reuben.
This genealogy ends in those two great patriots, Moses and Aaron; and comes in here to shew that they were Israelites, bone of their bone, and flesh of their flesh, whom they were sent to deliver, raised up unto them of their brethren, as Christ also should be, who was to be the prophet and priest, the Redeemer and law-giver of the house of Israel, and whose genealogy also like this was to be carefully preserved. The heads of the houses of three of the tribes are here named, agreeing with the accounts we had, Genesis 46:8-27. Reuben and Simeon seem to be mentioned only for the sake of Levi, from whom Moses and Aaron descended, and all the priests of the Jewish church.
 And these are the names of the sons of Levi according to their generations; Gershon, and Kohath, and Merari: and the years of the life of Levi were an hundred thirty and seven years.
The age of Levi, Kohath, and Amram, the father, grandfather, and great grandfather of Moses is here recorded; and they all lived to a great age, Levi to one hundred thirty seven, Kohath to one hundred thirty three, and Amram to one hundred thirty seven: Moses himself came much short of them, and fixed seventy or eighty for the ordinary stretch of human life. Psalms 90:10. For now Israel was multiplied, and become a great nation, and divine revelation was by the hand of Moses committed to writing, and no longer trusted to tradition; the two great reasons for the long lives of the patriarchs were ceased, and therefore from henceforward fewer years must serve men.
 And Amram took him Jochebed his father's sister to wife; and she bare him Aaron and Moses: and the years of the life of Amram were an hundred and thirty and seven years.
His father's sister — That is, kins-woman. So the Hebrew word is frequently used.
 And Aaron took him Elisheba, daughter of Amminadab, sister of Naashon, to wife; and she bare him Nadab, and Abihu, Eleazar, and Ithamar.
Aminadab — A prince of the tribe of Judah. The Levites might marry into any tribe, there being no danger of confusion or loss of inheritance thereby.
 These are that Aaron and Moses, to whom the LORD said, Bring out the children of Israel from the land of Egypt according to their armies.
According to their armies — Like numerous armies, in military order, and with great power. In the close of the chapter, he returns to his narrative, from which he had broken off somewhat abruptly verse 29.
 That the LORD spake unto Moses, saying, I am the LORD: speak thou unto Pharaoh king of Egypt all that I say unto thee.
Speak all that I say unto thee — As a faithful ambassador. Those that go on God's errand must not shun to declare the whole counsel of God.