Exodus 34:22 And thou shalt observe the
feast of weeks, of the firstfruits of wheat harvest, and the feast of ingathering at the year's end.
(this is the 2nd feast)
Deuteronomy 16:12-13
12 And thou shalt remember that thou wast a bondman in Egypt: and thou shalt observe and do these statutes.
13 Thou shalt observe the
feast of tabernacles seven days, after that thou hast gathered in thy corn and thy wine:
(this is the 3rd feast)
Deuteronomy 16:14-16
14 And thou shalt rejoice in thy feast, thou, and thy son, and thy daughter, and thy manservant, and thy maidservant, and the Levite, the stranger, and the fatherless, and the widow, that are within thy gates.
15 Seven days shalt thou keep a solemn feast unto the LORD thy God in the place which the LORD shall choose : because the LORD thy God shall bless thee in all thine increase, and in all the works of thine hands, therefore thou shalt surely rejoice.
16
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:
Exodus 12:7 And the children of Israel journeyed from Rameses to
Succoth, about six hundred thousand on foot that were men, beside children.
Numbers 3:5 And the children of Israel removed from Rameses, and pitched in
Succoth.
Tabernacles = 5521 cukkah sook-kaw' fem of 5520; a hut or lair:--**booth, cottage, covert, pavilion, tabernacle, tent.
5523 Cukkowth sook-kohth' or Cukkoth {sook-kohth'}; plural of 5521; booths; Succoth, the name of a place in Egypt and of three in Palestine:-- Succoth.
*5520 cok soke from 5526; a hut (as of entwined boughs); also a lair:-- covert, den, pavilion, tabernacle.
So I agree that the 3 feast mentioned have everything to do with the foreshadowing of salvation through Christ Jesus. They were all instituted before the Leviticus records. Then God tells Israel why this feast is to be observe in
*Leviticus 23:42-43
42 Ye shall dwell in booths seven days; all that are Israelites born shall dwell in
**booths:
43 That your generations may know that I made the children of Israel to dwell in
**booths, when I brought them out of the land of Egypt: I am the LORD your God.