Deuteronomy 16:5-9

CLV(i) 5 You cannot sacrifice the passover within any one of your gates which Yahweh your Elohim is giving to you, 6 but rather only in the place that Yahweh your Elohim shall choose to tabernacle His name. There shall you sacrifice the passover in the evening as the sun sets, the appointed time of your going forth from Egypt. 7 Then you will cook and eat in the place that Yahweh your Elohim shall choose, and you may turn around in the morning and go to your tents. 8 Six days shall you eat unleavened cakes, and on the seventh day, a day of restraint to Yahweh your Elohim, you shall do no occupational work at all. 9 You shall count off seven weeks for yourself. From the start of the scythe in the raised grain shall you start to count off seven weeks.