This image can be difficult to ‘read’ because it presents, not a static event, but a visual narrative: the narrative of Moses’s return journey to Egypt from his exile in Midian, as told in Exodus 4. The sequence begins in the middle background of the fresco, where Moses (dressed in yellow and green) departs from the house of his father-in-law, Jethro. He and his party travel along a winding path until—at the centre of the image—they meet the Angel of the Lord. This menacing figure holds a sword in one hand and grips Moses’s collar with the other, thus preventing Moses from continuing on his way. The narrative then proceeds to the right corner, where Zipporah (dressed in purple and blue) prepares to perform the circumcision that will spare her husband’s life and enable them to complete the journey into Egypt.
To truly appreciate the content of this fresco, the viewer must have a basic grasp of its situation within a wider theological programme. Located on the South Wall of the Sistine Chapel, Moses’s Journey into Egypt is the first in a series of frescoes showing events from the life of Moses; on the opposite wall is another fresco series depicting scenes from the life of Christ. The ‘message’ of the parallel cycles is that the new covenant of Christ continues and perfects the old covenant of the Mosaic law. Thus, each of the six frescoes showing scenes from the life of Moses is typologically paired with a corresponding event from Christ’s earthly ministry; the frescoes therefore communicate their theological content through the juxtapositions of each image with its parallel on the opposite wall. Within this programme, Moses’s Journey into Egypt is situated across from the Baptism of Christ, evoking the idea that the sacrament of baptism is a ‘spiritual circumcision’—a theological concept that can be traced back to the early Church Fathers.
19And the Lord said to Moses in Midʹian, “Go back to Egypt; for all the men who were seeking your life are dead.” 20So Moses took his wife and his sons and set them on an ass, and went back to the land of Egypt; and in his hand Moses took the rod of God.
21 And the Lord said to Moses, “When you go back to Egypt, see that you do before Pharaoh all the miracles which I have put in your power; but I will harden his heart, so that he will not let the people go. 22And you shall say to Pharaoh, ‘Thus says the Lord, Israel is my first-born son, 23and I say to you, “Let my son go that he may serve me”; if you refuse to let him go, behold, I will slay your first-born son.’ ”
24 At a lodging place on the way the Lord met him and sought to kill him. 25Then Zippoʹrah took a flint and cut off her son’s foreskin, and touched Moses’ feet with it, and said, “Surely you are a bridegroom of blood to me!” 26So he let him alone. Then it was that she said, “You are a bridegroom of blood,” because of the circumcision.
27 The Lord said to Aaron, “Go into the wilderness to meet Moses.” So he went, and met him at the mountain of God and kissed him. 28And Moses told Aaron all the words of the Lord with which he had sent him, and all the signs which he had charged him to do. 29Then Moses and Aaron went and gathered together all the elders of the people of Israel.