“Feasts” From Concise Bible Dictionary:
The feasts of Jehovah, as instituted under the law as given by Moses, partake more of the character of commemorations, or assemblies. of the congregation to celebrate special dealings of the Lord, and consequently special seasons—in the history of His people, being called “holy convocations.” A list of the yearly feasts is given in Leviticus 23. The first mentioned is the Sabbath, and if this is counted as one, by considering the Passover and the feast of unleavened bread as one there are seven in all—the perfect number. If the Sabbath is not included, as that was a weekly festival, being the rest of God, and on which the others were founded, then the Passover and the feast of unleavened bread may be counted as two, and still there are seven. There can be no doubt that these seven feasts were typical of the ways of blessing from the cross to the millennium. They stand thus:
Dates Lev. 23 Antitypes
The Sabbath. (Lev. 23:1-3)
Abib 14th Passover Feast. (Lev. 23:5-8) Christ our Passover is slain: “let us keep the feast,” that is of unleavened bread.
Abib 15th Feast of Unleavened Bread.
First Fruits (barley), “day after the Sabbath.” (Lev. 23:9-14) The Resurrection.
Zif. [Seven Sabbaths intervene]
Sivan. Pentecost: Feast of Weeks: First Fruits (wheat). (Lev. 23:15-22) Descent of the Holy Spirit and the Church formed.
Tammuz. Ab. Elul. [The present interval.]
Tisri 1St Feast of Trumpets. (Lev. 23:23-25) Israel awakened: they afflict their souls, receive their Messiah, and are brought into blessing in the millennium.
Tisri 10th Day of Atonement. (Lev. 23:26-32)
Tisri 15th Feast of Tabernacles: ingathering of the vintage. (Lev. 23:33-44)
These seven are called “the set feasts” (Num. 29:39; 1 Chron. 23. 31; 2 Chron. 31:3; Neh. 10:33). Also “holy convocations,” when the people assembled together to offer the various offerings, and thus be reminded of their association with the living God, to whom they owed all their blessings. To ensure this at least thrice in the year, it was enjoined that all the males should appear before the Lord three times in the year, and they must not appear empty. These times were at the Feast of Unleavened Bread (no doubt including the Passover); the Feast of Weeks, or of Harvest; and the Feast of Tabernacles, or “of Ingathering” (Ex. 23:14-17; Deut. 16:16). See PASSOVER, &c.
There are two other Feasts mentioned as yearly which were not apparently ordered of God. The 25th of Chisleu, the Feast of Dedication, instituted by Judas Maccabeus when the temple was re-dedicated after being defiled by Antiochus Epiphanes, B. C. 165 (John 10:22). The other, the Feast of Purim, on the 14th and 15th of Adar, when the Jews were delivered from the threatened destruction plotted by Haman (Esther 9:21, 26).