Deuteronomy 16:8-10

Complete Jewish Bible

⁸ For six days you are to eat matzah; on the seventh day there is to be a festive assembly for Adonai your God; do not do any kind of work.

⁹ “You are to count seven weeks; you are to begin counting seven weeks from the time you first put your sickle to the standing grain. ¹⁰ You are to observe the festival of Shavu‘ot [weeks] for Adonai your God with a voluntary offering, which you are to give in accordance with the degree to which Adonai your God has prospered you.