Deuteronomy 16:7-17

7And you shall roast it and eat it in the place the LORD your God will choose, and in the morning you shall return to your tents.

8For six days you must eat unleavened bread, and on the seventh day you shall hold a solemn assembly to the LORD your God, and you must not do any work.

9You are to count off seven weeks from the time you first put the sickle to the standing grain. 10And you shall celebrate the Feast of Weeks1 to the LORD your God with a freewill offering that you give in proportion to how the LORD your God has blessed you, 11and you shall rejoice before the LORD your God in the place He will choose as a dwelling for His Name—you, your sons and daughters, your menservants and maidservants, and the Levite within your gates, as well as the foreigner, the fatherless, and the widows among you.

12Remember that you were slaves in Egypt, and carefully follow these statutes.

13You are to celebrate the Feast of Tabernacles2 for seven days after you have gathered the produce of your threshing floor and your winepress. 14And you shall rejoice in your feast—you, your sons and daughters, your menservants and maidservants, and the Levite, as well as the foreigner, the fatherless, and the widows among you.

15For seven days you shall celebrate a feast to the LORD your God in the place He will choose, because the LORD your God will bless you in all your produce and in all the work of your hands, so that your joy will be complete.

16Three times a year all your men are to appear before the LORD your God in the place He will choose: at the Feast of Unleavened Bread,3 the Feast of Weeks,4 and the Feast of Tabernacles.5 No one should appear before the LORD empty-handed. 17Everyone must appear with a gift as he is able, according to the blessing the LORD your God has given you.