Old Testament

Leviticus 23:5-8
The Festivals of Passover and Unleavened Bread
5The first month, on the fourteenth day of the month, at twilight, is the Lord's Passover, 6and the fifteenth day of this month is the Festival of Unleavened Bread for the Lord. You shall eat unleavened bread for seven days. 7On the first day a holy convocation is to be proclaimed for you. You shall not do any work in your regular occupation. 8You shall present an offering by fire to the Lord for seven days. The seventh day shall be proclaimed as a holy convocation. You shall not do any work for your regular occupation.