Midrash sobre II Reyes 5:3

(Exodus 18:3) "and her two sons … in a foreign land": R. Yehoshua says "foreign": as stated (i.e., literally). R. Elazar Homadai says: in a land of foreign (gods, i.e., idolatry). Moses said: Since the whole world serves idolatry, I will serve Him who spoke and brought the (whole) world into being. For when Moses said to Yithro, Give me your daughter Tzipporah as a wife, Yithro answered, If you do what I ask of you, I will give her to you as a wife. Moses: What do you ask? Yithro: Your first son must serve idolatry. Thenceforward, they may serve (G d) in heaven. Moses accepted. Yithro: Swear. And he swore, as it is written (Exodus 2:21) "Vayoel Moses, etc.", this being an expression for swearing, as in (I Samuel 14:24) "Vayoel Saul the people" (in context: "And Saul beswore the people.") And it is written (II Kings 5:3) "Hoel (in context: "Swear") and take two talents, etc." Therefore, the angel came forward to kill Moses (viz. Exodus 4:24), whereupon (Ibid. 25) "Tzipporah took a flint and cut off the foreskin of her son … (26) "And he (the angel) let go of him." R. Elazar b. Azaryah says: Repulsive is the foreskin, by which the wicked are demeaned, viz. (Jeremiah 9:25) "for all the nations are uncircumcised, and all the house of Israel is uncircumcised of heart." R. Yishmael says: Great is circumcision over which thirteen covenants was made. R. Yossi Haglili says: Great is circumcision, which overrides the Sabbath, which is liable to kareth (cutting-off). R. Yehoshua b. Karcha says: Great is circumcision, laxity in which did not permit all of Moses' merits to protect him for even a short time. R. Nechemiah says: Great is circumcision, which overrides (non-cutting of) plague-spots (viz. Devarim 24:8). Rebbi says: Great is circumcision, all of Moses' merits not standing for him in his duress. When the L rd told him "Take out My people, the children of Israel from the land of Egypt," because he was lax for a short time in (the) circumcision (of his son), the angel sought to kill him, viz. (Exodus 4:24) "and he was on the way in the lodging, etc." R. Yossi says: G d forbid that tzaddikim should be lax in circumcision for even a short while, but Moses expounded: Shall he circumcise (his son) and journey (to Egypt) — that would involve a risk of life (for the child.) Shall he wait and circumcise — the L rd has said to him: "Go and take My people Israel out of Egypt." But (his lapse was that) he preoccupied himself with his lodging before circumcising, wherefore the L rd sought to kill him, viz.: "And he was on the way in the lodging, etc." R. Shimon b. Gamliel says: The angel did not seek to kill Moses, but the child, viz. (Ibid. 25) "for you are a groom of blood to me." Who is called a "groom" (in this context), the child or Moses? The child.