These are the heads of their fathers' houses: the sons of Reuben, the firstborn of Israel: Hanoch, Pallu, Hezron, and Carmi; these are the clans of Reuben. The sons of Simeon: Jemuel, Jamin, Ohad, Jachin, Zohar, and Shaul, the son of a Canaanite woman; these are the clans of Simeon. These are the names of the sons of Levi according to their generations: Gershon, Kohath, and Merari, the years of the life of Levi being 137 years. The sons of Gershon: Libni and Shimei, by their clans. The sons of Kohath: Amram, Izhar, Hebron, and Uzziel, the years of the life of Kohath being 133 years. The sons of Merari: Mahli and Mushi. These are the clans of the Levites according to their generations. Amram took as his wife Jochebed his father's sister, and she bore him Aaron and Moses, the years of the life of Amram being 137 years. The sons of Izhar: Korah, Nepheg, and Zichri. The sons of Uzziel: Mishael, Elzaphan, and Sithri. Aaron took as his wife Elisheba, the daughter of Amminadab and the sister of Nahshon, and she bore him Nadab, Abihu, Eleazar, and Ithamar. The sons of Korah: Assir, Elkanah, and Abiasaph; these are the clans of the Korahites. Eleazar, Aaron's son, took as his wife one of the daughters of Putiel, and she bore him Phinehas. These are the heads of the fathers' houses of the Levites by their clans.
These are the Aaron and Moses to whom the Lord said: “Bring out the people of Israel from the land of Egypt by their hosts.” It was they who spoke to Pharaoh king of Egypt about bringing out the people of Israel from Egypt, this Moses and this Aaron.
On the day when the Lord spoke to Moses in the land of Egypt, the Lord said to Moses, “I am the Lord; tell Pharaoh king of Egypt all that I say to you.” But Moses said to the Lord, “Behold, I am of uncircumcised lips. How will Pharaoh listen to me?”
Exodus 6:14-30
At first glance it seems odd - and even pointless - that a genealogy occupying many verses should be inserted into the story at this point, but we may be sure that there is some good purpose in it. And we may discern at least part of that purpose in the tracing of Moses' and Aaron's line from the patriarchs, as if to say, 'These men (26, 27) are not just any men, but stand in direct relationship to the patriarchs to whom the promise was given. They stand in an honourable line of succession. This is not a different story from that recorded in Genesis, but simply the next development of it.' God is, as it were, saying to us, 'Now let Me see if you know where you are in the history of the promise', and gives us a panoramic view of its 'movement' from the beginning up to this particular point. Furthermore, when we read through this list of names, we see that some of them have an unsavoury history, and we are reminded that, frail and human and sinful as this line and family was, it was caught up into a destiny of glory in the purpose of God. In the words at the beginning of the next chapter (7:1), 'I have made thee a god unto Pharaoh' at least suggest and give us a glimpse of the high and exalted destiny to which they were called. Finally, in the word 'god' we are introduced to the real realm in which the contest with Pharaoh was being fought out, the realm of principalities and powers, for from this point onwards we become deeply conscious of the supernatural at work with, on the one hand, the rod of God and, on the other, the dark powers of Pharaoh's magicians. The family line, then, becomes the meeting-place between two worlds, the arena in which the wrestling with principalities and powers becomes evident.