Exodus 22:29

22:29 “Do not hold back offerings from your granaries or your vats. You must give me the firstborn of your sons.

Exodus 34:22

34:22 “You must observe the Feast of Weeks – the firstfruits of the harvest of wheat – and the Feast of Ingathering at the end of the year.

Leviticus 23:9-21

The Presentation of First Fruits

23:9 The Lord spoke to Moses: 23:10 “Speak to the Israelites and tell them, ‘When you enter the land that I am about to give to you and you gather in its harvest, then you must bring the sheaf of the first portion of your harvest to the priest, 23:11 and he must wave the sheaf before the Lord to be accepted for your benefit – on the day after the Sabbath the priest is to wave it. 23:12 On the day you wave the sheaf you must also offer a flawless yearling lamb for a burnt offering to the Lord, 23:13 along with its grain offering, two tenths of an ephah of choice wheat flour mixed with olive oil, as a gift to the Lord, a soothing aroma, and its drink offering, one fourth of a hin of wine. 23:14 You must not eat bread, roasted grain, or fresh grain until this very day, until you bring the offering of your God. This is a perpetual statute throughout your generations in all the places where you live.

The Festival of Weeks

23:15 “‘You must count for yourselves seven weeks from the day after the Sabbath, from the day you bring the wave offering sheaf; they must be complete weeks. 23:16 You must count fifty days – until the day after the seventh Sabbath – and then you must present a new grain offering to the Lord. 23:17 From the places where you live you must bring two loaves of bread for a wave offering; they must be made from two tenths of an ephah of fine wheat flour, baked with yeast, as first fruits to the Lord. 23:18 Along with the loaves of bread, you must also present seven flawless yearling lambs, one young bull, and two rams. They are to be a burnt offering to the Lord along with their grain offering and drink offerings, a gift of a soothing aroma to the Lord. 23:19 You must also offer one male goat for a sin offering and two yearling lambs for a peace offering sacrifice, 23:20 and the priest is to wave them – the two lambs – along with the bread of the first fruits, as a wave offering before the Lord; they will be holy to the Lord for the priest.

23:21 “‘On this very day you must proclaim an assembly; it is to be a holy assembly for you. You must not do any regular work. This is a perpetual statute in all the places where you live throughout your generations.

Numbers 28:26-31

Firstfruits

28:26 “‘Also, on the day of the first fruits, when you bring a new grain offering to the Lord during your Feast of Weeks, you are to have a holy assembly. You must do no ordinary work. 28:27 But you must offer as the burnt offering, as a sweet aroma to the Lord, two young bulls, one ram, seven lambs one year old, 28:28 with their grain offering of finely ground flour mixed with olive oil: three-tenths of an ephah for each bull, two-tenths for the one ram, 28:29 with one-tenth for each of the seven lambs, 28:30 as well as one male goat to make an atonement for you. 28:31 You are to offer them with their drink offerings in addition to the continual burnt offering and its grain offering – they must be unblemished.

Deuteronomy 16:9-12

The Festival of Weeks

16:9 You must count seven weeks; you must begin to count them from the time you begin to harvest the standing grain. 16:10 Then you are to celebrate the Festival of Weeks before the Lord your God with the voluntary offering that you will bring, in proportion to how he has blessed you. 16:11 You shall rejoice before him – you, your son, your daughter, your male and female slaves, the Levites in your villages, the resident foreigners, the orphans, and the widows among you – in the place where the Lord chooses to locate his name. 16:12 Furthermore, remember that you were a slave in Egypt, and so be careful to observe these statutes.

Acts 2:1

The Holy Spirit and the Day of Pentecost

2:1 Now when the day of Pentecost had come, they were all together in one place.