Deuteronomy 16:1-3

CAB(i) 1 Observe the month of new grain, and you shall sacrifice the Passover to the Lord your God; because in the month of new grain you came out of Egypt by night. 2 And you shall sacrifice the Passover to the Lord your God, sheep and oxen in the place which the Lord your God shall choose to have His name called upon it. 3 You shall not eat leaven with it; seven days shall you eat unleavened bread with it, the bread of affliction, because you came forth out of Egypt in haste; that you may remember the day of your coming forth out of the land of Egypt all the days of your life.