Please explain Exodus 4:24 to 4:27. Thanks

The Torah describes a very unusual course of events in these passages. Moses stops off at an inn on his way back to Egypt. Suddenly, we find that G-d seeks to kill him, and that Zipporah, the wife of Moses, averts this attack by quickly circumcising their son, and touching the removed foreskin to her husband’s feet. Zipporah cries out, “You caused my bridegroom’s bloodshed.” He (the angel) releases Moses, and Zipporah cries out, “A bridegroom’s bloodshed was because of circumcision”.

The commentary on the Artscroll Stone Chumash explains this episode so beautifully that I thought to quote part of it:

Moses set out for Egypt with his family, including his newborn son, who had not yet been circumcised, and, because he was unconcerned about performing the circumcision in time, an angel was about to kill him. R’ Yose taught: Heaven forbid that Moses did not care about the circumcision. He was faced with a dilemma. Should he perform the circumcision before he went, and then take the child with him? – But the infant would be in danger for the first three days after the circumcision! Should he perform the circumcision and delay the trip for three days? – But G-d had commanded him to go! He decided to travel immediately [since G-d knew about the baby when He commanded him to go]; nevertheless he was held culpable because, when they arrived at an inn, he began making arrangements for his lodging instead of performing the circumcision without delay (Rashi from Nedarim 31b-32a). Even though he would have had to resume his trip to Egypt after the circumcision – thus putting the infant into new danger and justifying further delay – the inn was close enough to Egypt that the short trip would not endanger the child’s health (Ran, ibid).

An angel grasped Moses in such a way as to make Zipporah understand that the danger had been caused by Moses’ failure to circumcise the baby. Seeing that her husband was about to die because of his sin of omission, Zipporah circumcised the child, saving Moses’ life.

Although failure to perform a circumcision does not incur the death penalty, the most righteous people, such as Moses, are held to a higher standard of Divine accountability (Maharsha).