Deuteronomy 16:7-17

7And thou shalt roast and eat it in the place which Yhwh thy God shall choose: and thou shalt turn in the morning, and go unto thy tents. 8Six days thou shalt eat unleavened bread: and on the seventh day shall be a solemn assembly to Yhwh thy God: thou shalt do no work therein.1

9Seven weeks shalt thou number unto thee: begin to number the seven weeks from such time as thou beginnest to put the sickle to the grain. 10And thou shalt keep the feast of weeks unto Yhwh thy God with a tribute of a freewill offering of thine hand, which thou shalt give unto the Lord thy God, according as Yhwh thy God hath blessed thee:2 11And thou shalt rejoice before Yhwh thy God, thou, and thy son, and thy daughter, and thy manservant, and thy maidservant, and the Levite that is within thy gates, and the stranger, and the fatherless, and the widow, that are among you, in the place which Yhwh thy God hath chosen to place his name there. 12And thou shalt remember that thou wast a bondman in Egypt: and thou shalt observe and do these statutes.

13Thou shalt observe the feast of tabernacles seven days, after that thou hast gathered in thy threshingfloor and thy wine:3 14And thou shalt rejoice in thy feast, thou, and thy son, and thy daughter, and thy manservant, and thy maidservant, and the Levite, the stranger, and the fatherless, and the widow, that are within thy gates. 15Seven days shalt thou keep a solemn feast unto Yhwh thy God in the place which Yhwh shall choose: because Yhwh thy God shall bless thee in all thine increase, and in all the works of thine hands, therefore thou shalt surely rejoice.

16Three times in a year shall all thy males appear before Yhwh thy God in the place which he shall choose; in the feast of unleavened bread, and in the feast of weeks, and in the feast of tabernacles: and they shall not appear before Yhwh empty: 17Every man shall give as he is able, according to the blessing of Yhwh thy God which he hath given thee.4