Deuteronomy 16:5-9

EJ2000(i) 5 Thou may not sacrifice the passover within any of thy gates (or within any of thy towns) which the LORD thy God gives thee 6 but at the place which the LORD thy God shall choose to cause his name to dwell in; there thou shalt sacrifice the passover in the evening, at the going down of the sun, at the appointed time when thou came forth out of Egypt. 7 And thou shalt roast and eat it in the place which the LORD thy God shall choose, and thou shalt turn in the morning and return unto thy tabernacles. 8 Six days thou shalt eat unleavened bread, and on the seventh day shall be a solemn feast unto the LORD thy God; thou shalt do no work in this. 9 Seven weeks shalt thou number unto thee; begin to number the seven weeks from such time as thou shalt begin to put the sickle to the grain.