It is possible to read through these verses without paying attention to how they are related to the narrative at hand. Moses had just been given instructions to lead the people of Israel out of Egypt. He has been armed with signs and wonders. Then we are confronted with God seeking to kill him. His sin is not stated, but the read gives us clues. Moses was to lead Israel out of Egypt and to be an example to Pharaoh and all Egypt. His personal life had to be in order before he could lead others. You don’t play games with God while you lead others. That should all be in caps for emphasis. Someone says ”his personal life had to be together before he could direct the spiritual lives of the Hebrew people”. Isn’t that what is required of every minister? It does appear that Moses had neglected the sacred rite of the covenant of circumcision. Zipporah, Moses’s wife was from Midian. She perhaps thought the practice inhumane, especially to a child. She calls him, a bloody husband. To God, the disobedience would make Moses unfit to lead. It had to be sorted out. God wanted to let Moses know you can’t lead without following instructions yourself. Every minister should read that. It was Moses’s duty to have taught Zipporah. We must love God without hypocrisy( Rom.12:9).
And it came to pass by the way in the inn, that the Lord met him, and sought to kill him. Then Zipporah took a sharp stone, and cut off the foreskin of her son, and cast it at his feet, and said, Surely a bloody husband art thou to me. So he let him go: then she said, A bloody husband thou art, because of the circumcision. Exodus 4:24-26 KJV