Leviticus 23:5-7

New International Version - UK

⁵ the Lord’s Passover begins at twilight on the fourteenth day of the first month. ⁶ On the fifteenth day of that month the Lord’s Festival of Unleavened Bread begins; for seven days you must eat bread made without yeast. ⁷ On the first day hold a sacred assembly and do not do any of your ordinary work.