Shavu'ot
Hag Matan Toratenu
Festival of Giving of Our Law
Pentecost

Shavu'ot is a Jewish holiday on the 6th of Sivan, the third month in the Hebrew calendar, which occurs in late May or early June. It is the second of three pilgrimage holidays each year: Passover (Pesach), Shavuot, and Sukkot, which means that during these times Jews from all over Israel would travel to Jerusalem to observe these festivals.

According to custom, it celebrates Moses receiving the Ten Commandments on Mount Sinai. The sages said that we receive the truth of the Torah (Ten Commandments) every day, but Shavu'ot reminds us of the day G-d first gave it to us.

The Bible actually only refers to Shavu'ot as agricultural holidays and doesn't tie it to the giving of the Ten Commandments. In Exodus it is known as Hag ha-katzir, the feast of the harvest:

Three times thou shalt keep a feast unto me in the year. Thou shalt keep the feast of unleavened bread: (thou shalt eat unleavened bread seven days, as I commanded thee, in the time appointed of the month Abib; for in it thou camest out from Egypt: and none shall appear before me empty:) And the feast of harvest, the firstfruits of thy labors, which thou hast sown in the field: and the feast of ingathering, which is in the end of the year, when thou hast gathered in thy labors out of the field. Three items in the year all thy males shall appear before the L-RD G-d. Thou shalt not offer the blood of my sacrifice with leavened bread; neither shall the fat of my sacrifice remain until the morning. The first of the firstfruits of thy land thou shalt bring into the house of the L-RD thy G-d. Thou shalt not seethe a kid in his mother's milk.

Exodus 23:14-19

In Leviticus it is referred to as Hag Hashavuot, the festival of weeks and as Yom ha-birkuim, the day of the first fruits. This refers to when the barley was harvested and brought to the Temple in Jerusalem before the beginning of the wheat season which begins the first week of Sivan.

And the L-RD spoke to Moses, saying, Speak to the children of Israel, and say to them: When you come into the land which I give to you, and reap its harvest, then you shall bring a sheaf of the first fruits of your harvest to the priest. He shall wave the sheaf before the L-RD, to be accepted on your behalf; on the day after the Sabbath the priest shall wave it. And you shall count for yourselves from the day after the Sabbath, from the day that you brought the sheaf of the wave offering: seven Sabbaths shall be completed. Count fifty days to the day after the seventh Sabbath; then you shall offer a new grain offering to the L-RD.

Leviticus 23:9-16

Shavu'ot is to be celebrated exactly 49 days or seven weeks after the second day of Passover, the day of the first Omer, or the offering of the barley. The ultra-Orthodox Jews observe the period between Passover and Shavu'ot in preparing for the receiving of the Torah and do not participate in frivolous activities. They do not marry, listen or play music, or cut their hair.

Many adults and children who are old enough will stay up the entire first night of Shavu'ot and study the Torah and then go to the synagogue to pray first thing in the morning. By custom at least one dairy meal is eaten as a reminder that G-d promised that Israel would be a land flowing with milk and honey (Exodus 3:8).

The Book of Ruth is also read sometime during the holiday. Ruth was a Moabite woman who was the great grandmother of King David and it is believed that she was born and died on Shavu'ot. The story of Ruth takes place during the barley and wheat harvests in Judea. Work is not permitted on Shavu'ot.  Often Akdamot, a book written by Rabbi Meir ben Isaac in the 11th century is read.  The books talks about how it will be once the Messiah will come.

In the United States, confirmation services are held on Shavu'ot and the children often start their Jewish education on Shavu'ot.