Deuteronomy 16:1-3

“Observe the month of Abib and celebrate the Passover to the LORD your God, for in the month of Abib the LORD your God brought you out of Egypt by night. You shall sacrifice the Passover to the LORD your God from the flock and the herd, in the place where the LORD chooses to establish His name. You shall not eat leavened bread with it; seven days you shall eat with it unleavened bread, the bread of affliction (for you came out of the land of Egypt in haste), so that you may remember all the days of your life the day when you came out of the land of Egypt.