Cross reference
Exodus 4:25
25 Then Zipporah took a sharp stone, and cutting off the skin of her son's private parts, and touching his feet with it, she said, Truly you are a husband of blood to me.
Joshua 5:2-3
2 At that time the Lord said to Joshua, Make yourself stone knives and give the children of Israel circumcision a second time.
3 So Joshua made stone knives and gave the children of Israel circumcision at Gibeath-ha-araloth.
Genesis 17:14
14 And any male who does not undergo circumcision will be cut off from his people: my agreement has been broken by him.
2 Samuel 16:7
7 And Shimei said, with curses, Be gone, be gone, you man of blood, you good-for-nothing: