Albert Barnes Commentary Leviticus 23:42

"Ye shall dwell in booths seven days; all that are home-born in Israel shall dwell in booths;" — Leviticus 23:42 (ASV)

Booths - According to Jewish tradition, what were used at the Feast of Tabernacles were strictly “tabernacula,” structures of boards, with a covering of branches.

The “booth” in which the Israelite kept the Feast, and the “tent” which was his ordinary dwelling in the wilderness, had this in common—they were places for temporary stays, and they belonged to camp life. The seven days of dwelling in the booths of the festival was therefore a fitting symbol of the forty years of dwelling in tents in the wilderness. The Feast might well become the appointed memorial of this period of their history for future generations.

All that are Israelites born - The omission of the foreigners in this command is remarkable. Perhaps the intention was that on this joyous occasion they were to be hospitably entertained as guests .