Deuteronomy 16:3-5

New Life Version

³ Do not eat bread made with yeast. For seven days eat bread made without yeast, the bread of sorrow, because you came out of the land of Egypt in a hurry. So all the days of your life you will remember the day when you came out of the land of Egypt. ⁴ For seven days there is to be no yeast around in all your land. And none of the flesh you give in worship on the evening of the first day will be kept through the night until morning. ⁵ You are not allowed to give the Passover gift in any of your towns the Lord your God gives you.