21 Again the Lord said to Moses, “Now that you are going back to Egypt, be sure to perform before the king all the miracles which I have given you the power to do. But I will make the king stubborn, and he will not let the people go.
22 Then you must tell him that I, the Lord, say, ‘Israel is my firstborn son.
23 I told you to let my son go, so that he might worship me, but you refused. Now I am going to kill your firstborn son.’ ”
24 At a camping place on the way to Egypt, the Lord met Moses and tried to kill him.
25-26 Then Zipporah, his wife, took a sharp stone, cut off the foreskin of her son, and touched Moses' feet with it. Because of the rite of circumcision she said to Moses, “You are a husband of blood to me.” And so the Lord spared Moses' life.
27 Meanwhile the Lord had said to Aaron, “Go into the desert to meet Moses.” So he went to meet him at the holy mountain; and when he met him, he kissed him.
28 Then Moses told Aaron everything that the Lord had said when he told him to return to Egypt; he also told him about the miracles which the Lord had ordered him to perform.