Celebrate the Feast of Tabernacles for seven days after you have gathered the produce of your threshing floor and your winepress.  Be joyful at your Feast - you, your sons and daughters, your menservants and maidservants, and the Levites, the aliens, the fatherless and the widows who live in yhour towns.  For seven days celebrate the Feast to the LORD your God at the place the LORD will choose.  For the LORD your God will bless you in all your harvest and in all the work of your hands, and your joy will be complete.  (Deuteronomy 16:13-17)

As Moses is giving the children of Israel his farewell address, he reminds them of the instructions God gave at Sinai.  Three times each year they were required to appear before Him in the place that He selected.  Passover, Pentecost (Feast of Weeks), and Tabernacles.  In our experience we tend to focus on Passover, because of Easter, and Pentecost, because of Acts Chapter Two.  We tend to pay little attention to Tabernacles.  As usual this is unfortunate.  It was in the context of this feast that Jesus makes a tremendous promise that we hold onto to this day:  "On the last and greatest day of the Feast, Jesus stood and said in a loud voice, 'If anyone is thirsty, let him come to me and drink.  Whoever believes in me, as the Scripture has said, streams of living water will flow from within him.'  By this he meant the Spirit, whom those who believed in him were later to receive.  Up to that time the Spirit had not been given, since Jesus had not yet been glorified."  (John 7:37-39)

This feast was a time of thanksgiving that was celebrated at the end of the final harvest season.  The people spent seven days living in makeshift booths made with tree branches to remember God's fatihfulness during their wilderness wanderings.  Some believe that the first "thanksgiving" observed by the Pilgrims was actually a Tabernacle celebration.  While some observances were meant to be somber commemorations, this was to be a joyful celebration of God's faithfulness.  by the way, the Feast of Tabernacles starts this Saturday, October 3.