Exodus 4:24-26 fits well into the overall picture of the Abrahamic covenant. From Exodus 2:23-25, you will notice that the basis for the Exodus was God’s promises to Abraham in the Abrahamic covenant. On the basis of this covenant, Israel would be rescued out of Egypt. Then, in Exodus 3-4, God calls Moses to deliver Israel out of Egypt. By the time we get to the segment in question, Moses was finally being obedient in heading for Egypt with his wife and sons (Ex. 4:20).
Moses was married to a Midianite woman, and the Midianites did not practice circumcision. In Exodus 4:24-26, only one son was circumcised, which would indicate that when the first son was born, Moses had him circumcised, but his wife may not have liked what she saw. Therefore, when the second son was born, Moses failed to circumcise him, which was in disobedience to the Abrahamic covenant as detailed in Genesis 17. The failure to circumcise could be punishable by death. Now, the question arises: If God was going to save Israel on the basis of the Abrahamic covenant, how could He use someone who was clearly being disobedient to that covenant? Hence, God struck Moses with a very debilitating sickness of some kind that brought him close to death and made him too weak to move. His wife recognized what the situation was. Realizing that to save her husband’s life she would have to be the one to circumcise that second son, since Moses could not do so, she took a flint and performed the circumcision. By so doing, she saved the life of her husband, yet, she was not happy with what she had to do and kept calling Moses “a bloody bridegroom.”
Because of her negativism over the act of circumcision, the wife and sons were sent back to Midian and did not travel with Moses to Egypt. Therefore, they failed to see all of the supernatural works that God performed during the time of the Exodus. When the Jewish people finally arrived at Mount Sinai, Moses’ father-in-law had to bring his wife and sons to Moses at Mount Sinai. Moses’ failure to obey the sign of God’s promises to Abraham brought discord and sadness to the lives of his entire family.