Leviticus 23:7-16

7 aOn the first day you shall have a holy convocation; you shall not do any ordinary work. 8But you shall present a food offering to the Lord for seven days. On the seventh day is a holy convocation; you shall not do any ordinary work.”

The Feast of Firstfruits

9And the Lord spoke to Moses, saying, 10Speak to the people of Israel and say to them, bWhen you come into the land that I give you and reap its harvest, you shall bring the sheaf of cthe firstfruits of your harvest to the priest, 11and he shall dwave the sheaf before the Lord, so that you may be accepted. On the day after the Sabbath the priest shall wave it. 12And on the day when you ewave the sheaf, you shall offer a fmale lamb a year old without blemish as a burnt offering to the Lord. 13 gAnd the grain offering with it shall be two tenths of an ephah
An  ephah was about 3/5 bushel or 22 liters
of fine flour mixed with oil, a food offering to the Lord with a pleasing aroma, iand the drink offering with it shall be of wine, a fourth of a hin.
A  hin was about 4 quarts or 3.5 liters
14And you shall eat neither bread nor grain kparched or lfresh until this same day, until you have brought the offering of your God: it is a statute forever throughout your generations in all your dwellings.

The Feast of Weeks

15 m“You shall count seven full weeks from the day after the Sabbath, from the day that you brought the sheaf of the nwave offering. 16You shall count ofifty days to the day after the seventh Sabbath. Then you shall present a grain offering of pnew grain to the Lord.
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