Exodus 12:15-16

12:15 For seven days you must eat bread made without yeast. Surely on the first day you must put away yeast from your houses because anyone who eats bread made with yeast from the first day to the seventh day will be cut off from Israel.

12:16 On the first day there will be a holy convocation, and on the seventh day there will be a holy convocation for you. You must do no work of any kind on them, only what every person will eat – that alone may be prepared for you.