Exodus 13:5-7

5When Adonai brings you into the land of the Canaanites, the Hittites, the Amorites, the Hivites and the Jebusites, which He swore to your fathers to give you, a land flowing with milk and honey, you are to observe this service during this month.

6For seven days you are to eat matzah , and the seventh day is to be a feast to Adonai.

7Matzot is to be eaten throughout the seven days, and no hametz is to be seen among you, nor within any of your borders.