The episode of Zipora’s emergency circumcision of her son at a wayside inn seems to defy interpretation. Who is it that God sought to kill, and why? We can begin to make sense of this story only when we realize that it has been lifted out of its proper place in the wider narrative; chronologically, it belongs much later, during the plague against the firstborn. But then, why do we find it here, at the very beginning of Moshe’s mission?
When Moshe is told to go back to Egypt and free the Israelites, he asks “What if they won’t believe me?” God’s answer is in the form of symbolic wonders, each of which involve things becoming something contrary to their nature: a healthy hand that becomes leprous, and a staff that becomes a snake. But why a snake? The choice of this particular animal is no coincidence. In fact, it’s the key to Moshe’s mission!