21The LORD instructed Moses, “When you go back to Egypt, see that you perform before Pharaoh all the wonders that I have put within your power. But I will harden his heart so that he will not let the people go.
22Then tell Pharaoh that this is what the LORD says: ‘Israel is My firstborn son,
23and I told you to let My son go so that he may worship Me. But since you have refused to let him go, behold, I will kill your firstborn son!’”
24Now at a lodging place along the way, the LORD met Moses and was about to kill him.
25But Zipporah took a flint knife, cut off her son’s foreskin, and touched it to Moses’ feet. “Surely you are a bridegroom of blood to me,” she said.
26So the LORD let him alone. (When she said, “bridegroom of blood,” she was referring to the circumcision.)
27Meanwhile, the LORD had said to Aaron, “Go and meet Moses in the wilderness.” So he went and met Moses at the mountain of God and kissed him.
28And Moses told Aaron everything the LORD had sent him to say, and all the signs He had commanded him to perform.
29Then Moses and Aaron went and assembled all the elders of the Israelites,
30and Aaron relayed everything the LORD had said to Moses. And Moses performed the signs before the people,
31and they believed. And when they heard that the LORD had attended to the Israelites and had seen their affliction, they bowed down and worshiped.
— Exodus 4:21-31