Sukkot 5783, Day 1

"Again the L-rd spoke to Moses, saying, 34 “Speak to the sons of Israel, saying, ‘On the fifteenth of this seventh month is the Feast of Booths for seven days to the L-rd. 35 On the first day is a holy convocation; you shall not do any laborious work. 36 For seven days you shall present an offering by fire to the L-rd."

Leviticus 23:33-36