Parshat Bo

The last three of the Ten Plagues are visited on Egypt: a swarm of locusts devours all the crops and greenery; a thick, palpable darkness envelops the land; and all the firstborn of Egypt are killed at the stroke of midnight of the 15th of the month of Nissan.

G‑d commands the first mitzvah to be given to the people of Israel: to establish a calendar based on the monthly rebirth of the moon. The Israelites are also instructed to bring a “Passover offering” to G‑d: a lamb or kid goat is to be slaughtered, and its blood sprinkled on the doorposts and lintel of every Israelite home, so that G‑d should pass over these homes when He comes to kill the Egyptian firstborn. The roasted meat of the offering is to be eaten that night together with matzah (unleavened bread) and bitter herbs.