The Ten Plagues reach their climax with the death of the firstborn. This last plague is announced with a set of instructions to prepare the Israelites for the impeding Exodus, together with a commandment to change the calendar.

The latter seems strangely placed: why disrupt the story with a directive to commemorate an event that has not yet taken place? Why worry the Israelites with instructions about the calendar when they are focused on escaping from Egyptian slavery?

According to the Italian commentator Ovadia Sforno, it signifies that when the Israelites become a free people, their time will be their own. We, however, could see it as an encouragement for the Israelites to take some responsibility in their own liberation; a sign that the Exodus was not meant to be a passive rescue mission.

After all, history must always be acted out by its human protagonists. The Israelites must therefore actively involve themselves in the last plague: firstly by inwardly differentiating themselves from Egyptian culture, and secondly by outwardly identifying themselves as Israelites, for God can take the Israelites out of Egypt; but only the Israelites can take Egypt out of themselves.

That process started with accepting a new concept of time, a new calendar. It is the first conscious act of differentiation; a setting oneself apart from the surrounding Egyptian culture. In adopting a new calendar, they did not just exercise their newly found freedom (to do as they please) rather, they actively chose to live according to a different narrative.

Daubing blood on the doorpost was the outward identification, but it had to be preceded by the adoption of a new calendar that was based on a narrative of events that had not even happened yet, for it indicated a willingness to shape a new identity, and a new history that follows the moral imperative of God; a narrative in which the suppression of another people has no place.

From now on the Israelites will no longer be B’nei Yisrael solely because they are descendants of Israel/Jacob. They are Israelites, because they actively chose to be a people with a future and a faith bound up in a story that would define and inspire them for generations to come, leading them then and us from Egypt to Sinai on to the Eretz Yisrael.