Well, let’s read the passage. This is after God had appeared to Moses and called him to deliver the people of Israel from Egypt. Moses had spent forty years shepherding the flocks of his father-in-law in the land of Midian. Now he is returning to Egypt to deliver Israel from bondage to Pharaoh. And so we read:
At a lodging place on the way the LORD met him and sought to put him to death.
Now this comes out of the blue. What in the world is going on here? Why did God seek to kill him? Well, as we continue reading we get some clues.
25 Then Zipporah took a flint and cut off her son’s foreskin and touched Moses’ feet with it [some translations say, threw it at Moses’ feet] and said, “Surely you are a bridegroom of blood to me!” 26 So he let him alone. It was then that she said, “A bridegroom of blood,” because of the circumcision.
Remember, this occurred when Moses was on his way from Midian to Egypt to fulfill God’s commission to deliver Israel. He was called to be the leader of Israel, but he had failed to obey God by applying the sign of the covenant to his own son. This was a very serious failure on his part.
In the New Testament, St. Paul wrote concerning the qualification of elders, “if someone does not know how to manage his own household, how will care for God’s church?” (1 Tim. 3:5)
Moses had been called by God to be Israel’s deliverer and law-giver, but he himself had failed to carry out the law of circumcision with respect to his own son. He had not managed his own household well, and therefore was not fit to “take care of God’s church.”
God was about to bring Israel out of bondage for the sake of his covenant with Abraham, and to confirm that covenant with his descendants. We read in Exodus 2:24, “And God heard their groaning, and God remembered his covenant with Abraham, with Isaac, and with Jacob.” God was acting for the sake of the covenant. But Moses had neglected the sign and seal of the covenant. This was a serious offense. God had told Abraham, “Any uncircumcised male who is not circumcised in the flesh of his foreskin shall be cut off from his people; he has broken my covenant” (Gen. 17:14).
We may wonder how it was that Moses could have been guilty of such neglect. I would venture this as an explanation: Moses had two sons whom he took along with his wife back to Egypt (cf. Ex. 4:20; 18:3). When God confronted him, his wife Zipporah circumcised just one of their sons. It says that she “cut off her son’s [singular] foreskin.” This suggests that the other son had already been circumcised. My guess is that after the circumcision of Gershom, the firstborn, Zipporah (who was a Midianite and not accustomed to the practice of circumcision) was unwilling to have the bloody and painful rite repeated on her second son, Eliezer. Her reaction indicates a revulsion on her part to her son’s circumcision. And Moses, in weakness, caved in to his wife’s wishes and didn’t circumcise his second son. But before he could proceed with the fulfillment of his mission (not to say his life!), Moses had to comply with the command of God and apply the sign and seal of the covenant to his second born.
While his second born was left uncircumcised, Moses showed that he had more regard for his wife’s opinions than he had for God’s command. How could he be thought fit to lead Israel? How could he be Israel’s lawgiver? How could he be the messenger of the covenant? How could he enforce obedience to God’s law, if he was himself neglectful of so basic a command of God?
Besides, if Moses couldn’t stand up to his wife, how was he going to stand up to Pharaoh?!
Now the text doesn’t say so, but it seems probable to me that God had talked to Moses about this previously. Obviously God knew when he called Moses that his son was uncircumcised. My guess is that he told Moses that he better get his house in order by circumcising his son before he left for Egypt, but Zipporah objected and Moses failed to act. Maybe he hoped God would forget about it. Maybe he hoped God wasn’t serious. I don’t know. But for whatever reason Moses failed to obey. So God comes to him and says, “Look, Mo, unless you do what I say, you’re a dead man.”
I’ve always imagined that God had Moses pinned up against the wall, and Moses called out to his wife and said, “Honey get the knife and circumcise little Eliezer, because if he doesn’t lose his foreskin, I’m going to lose my head!”
And as soon as Moses complied, God let him live.