Leviticus 23:1-22

The LORD spoke to Moses, saying: Speak to the people of Israel and say to them: These are the appointed festivals of the LORD that you shall proclaim as holy convocations, my appointed festivals. The Sabbath, Passover, and Unleavened Bread
(Num 28.16—25)
Six days shall work be done; but the seventh day is a sabbath of complete rest, a holy convocation; you shall do no work: it is a sabbath to the LORD throughout your settlements.
These are the appointed festivals of the LORD, the holy convocations, which you shall celebrate at the time appointed for them. In the first month, on the fourteenth day of the month, at twilight, there shall be a passover offering to the LORD, and on the fifteenth day of the same month is the festival of unleavened bread to the LORD; seven days you shall eat unleavened bread. On the first day you shall have a holy convocation; you shall not work at your occupations. For seven days you shall present the LORD's offerings by fire; on the seventh day there shall be a holy convocation: you shall not work at your occupations.
The Offering of First Fruits
The LORD spoke to Moses: Speak to the people of Israel and say to them: When you enter the land that I am giving you and you reap its harvest, you shall bring the sheaf of the first fruits of your harvest to the priest. He shall raise the sheaf before the LORD, that you may find acceptance; on the day after the sabbath the priest shall raise it. On the day when you raise the sheaf, you shall offer a lamb a year old, without blemish, as a burnt offering to the LORD. And the grain offering with it shall be two-tenths of an ephah of choice flour mixed with oil, an offering by fire of pleasing odor to the LORD; and the drink offering with it shall be of wine, one-fourth of a hin. You shall eat no bread or parched grain or fresh ears until that very day, until you have brought the offering of your God: it is a statute forever throughout your generations in all your settlements.
The Festival of Weeks
(Ex 34.22; Num 28.26—31; Deut 16.9—10)
And from the day after the sabbath, from the day on which you bring the sheaf of the elevation offering, you shall count off seven weeks; they shall be complete. You shall count until the day after the seventh sabbath, fifty days; then you shall present an offering of new grain to the LORD. You shall bring from your settlements two loaves of bread as an elevation offering, each made of two-tenths of an ephah; they shall be of choice flour, baked with leaven, as first fruits to the LORD. You shall present with the bread seven lambs a year old without blemish, one young bull, and two rams; they shall be a burnt offering to the LORD, along with their grain offering and their drink offerings, an offering by fire of pleasing odor to the LORD. You shall also offer one male goat for a sin offering, and two male lambs a year old as a sacrifice of well-being. The priest shall raise them with the bread of the first fruits as an elevation offering before the LORD, together with the two lambs; they shall be holy to the LORD for the priest. On that same day you shall make proclamation; you shall hold a holy convocation; you shall not work at your occupations. This is a statute forever in all your settlements throughout your generations.
When you reap the harvest of your land, you shall not reap to the very edges of your field, or gather the gleanings of your harvest; you shall leave them for the poor and for the alien: I am the LORD your God.