Leviticus 23:3, 32

“ ‘There are six days for you to work, but the seventh day will be a special day of rest. It is a day for a holy meeting; you must not do any work. It is a Sabbath to the LORD in all your homes.

It will be a special day of rest for you, and you must deny yourselves. You will start this special day of rest on the evening after the ninth day of the month, and it will continue from that evening until the next evening.”