The seven feasts of Israel are listed in the twenty-third chapter of the Book of Leviticus in the Old Testament. They were not all feasts, as we think of the word feast. However, they were all observances in which the people of Israel were called together by the Lord.
Here is the list of the seven feasts, as found in the Book of Leviticus, Chapter 23:
Passover—In the fourteenth day of the first month at even is the Lord’s Passover (verse 5).
Unleavened Bread—And on the fifteenth day of the same month is the feast of unleavened bread to the Lord: seven days ye must eat unleavened bread (verse 6).
Firstfruits—Speak to the children of Israel, and say to them, When ye be come into the land that I give to you, and will reap the harvest thereof, then ye will bring a sheaf of the firstfruits of your harvest to the priest (verse 10).
Pentecost—And ye will count to you from the morrow after the sabbath, from the day that ye brought the sheaf of the wave offering; seven sabbaths will be complete: even to the morrow after the seventh sabbath will ye number fifty days; and ye will offer a new meat offering to the Lord (verses 15,16).
Trumpets—Speak to the children of Israel, saying, In the seventh month, in the first day of the month, will ye have a sabbath, a memorial of blowing of trumpets, an holy convocation (verse 24).
Day of Atonement—Also on the tenth day of this seventh month there will be a day of atonement: it will be an holy convocation to you; and ye will afflict your souls, and offer an offering made by fire to the Lord (verse 27).
Tabernacles—Speak unto the children of Israel, saying, The fifteenth day of this seventh month will be the feast of tabernacles for seven days to the Lord (verse 34).
The seven feasts of Israel were grouped into three great annual convocations. Three times in a year shall all thy males appear before the Lord thy God in the place which he shall choose; in the feast of unleavened bread, and in the feast of weeks, and in the feast of tabernacles: and they shall not appear before the Lord empty: (Deuteronomy 16:16)
In terms of our present calendar, the three annual celebrations were as follows:
Feast of Unleavened Bread (April):
2. Unleavened Bread
Feast of Weeks (May):
Feast of Tabernacles (September-October):
6. Day of Atonement