follows: Psalms and each recount differing arrangements of seven plagues. recalls plagues of (1) blood, (2) flies, (3) frogs, (4) locusts, (5) hail, (6) livestock, and (7) firstborn, but not plagues of lice, boils, or darkness. recalls plagues of (1) darkness, (2) blood, (3) frogs, (4) flies and lice, (5) hail, (6) locusts, and (7) firstborn, but not plagues of livestock or boils. Exodus chapters 12–13 Passover and 43–50 and refer to the Festival of Passover. In the Hebrew Bible, Passover is called: "Passover" (Pesach, ); "The Feast of Unleavened Bread" (Chag haMatzot, ); and "A holy convocation" or "a solemn assembly" (mikrah kodesh, ). Some explain the double nomenclature of "Passover" and "Feast of Unleavened Bread" as referring to two separate feasts that the Israelites combined sometime between the Exodus and when the Biblical text became settled. and indicate that the dedication of the firstborn also became associated with the festival. Some believe that the "Feast of Unleavened Bread" was an agricultural festival at which the Israelites celebrated the beginning of the grain harvest. Moses may have had this festival in mind when in and he petitioned Pharaoh to let the Israelites go to celebrate a feast in the wilderness. "Passover," on the other hand, was associated with a thanksgiving sacrifice of a lamb, also called "the Passover," "the Passover lamb," or "the Passover offering." , , and and 5, and direct "Passover" to take place on the evening of the fourteenth of Aviv (Nisan in the Hebrew calendar after the Babylonian captivity). , , , and confirm that practice. , , and , , and direct the "Feast of Unleavened Bread" to take place over seven days and and direct that it begin on the fifteenth of the month. Some believe that the propinquity of the dates of the two festivals led to their confusion and merger. and 27 link the word "Passover" (Pesach, ) to God's act to "pass over" (pasach, ) the Israelites' houses in the plague of the firstborn. In the Torah, the consolidated Passover and Feast of Unleavened Bread thus commemorate the Israelites' liberation from Egypt. Benjamin Sommer saw in and a case in which one Biblical author explicitly interpreted another Biblical text. Both texts provide regulations concerning the Passover sacrifice, but the regulations differ. instructed the Israelites to boil the Passover sacrifice. Sommer argued that takes issue with on this point, however, warning