Leviticus 23:6-8

6On the fifteenth day of the same month is the Feast of Matzot to Adonai. For seven days you are to eat matzah .

7On the first day you are to have a holy convocation and you shall do no regular work.

8Instead you are to present an offering made by fire to Adonai for seven days. On the seventh day is a holy convocation, when you are to do no regular work.”