Leviticus 23:41 (NIV)
41 Celebrate this as a festival to the LORD for seven days each year. This is to be a lasting ordinance for the generations to come; celebrate it in the seventh month.
42 Live in booths for seven days...
The biggest party of the Jewish calendar year was called the Feast of Tabernacles, a 7 day celebration described in Leviticus 23:34-44. It was so big and popular people also just called it the "Feast" (e.g. John 7:37). People were to celebrate this festival by moving out of their normal homes and living in tents decorated with tree branches (Lev 23:40).
God instituted the Feast of Tabernacles as a way for the Jews to celebrate the entire year of harvest (Lev 23:39), to commemorate how their ancestors had wandered in the wilderness in tents (Lev 23:43) and to simply be refreshed and have fun ("rejoice before the Lord your God for seven days" (Lev 23:40).
Later on the Jews added other traditions to the Feast. For example, during the Feast the Jews would draw water from the Pool of Siloam and pour it on the altar. It was their way of remembering how God drew water from a rock to quench His people's thirst when they were wandering in the desert (Numbers 20). With that in mind, we can appreciate better why Jesus, on the last day of the Feast, stood up and shouted, "If anyone is thirsty, let him come to me and drink...and streams of living water will flow from within him." (John 7:37-39)
From the Feast of Tabernacles, we can learn three important lessons:
1. God wants us to take time each year to rest, get refreshed and celebrate by doing something we don't normally do. Vacation is a godly thing! Joy is a God thing!
2. God wants us to remember and appreciate the experiences of our ancestors. That doesn't mean worship them, but never forget where you came from and the sacrifices that your ancestors made to make your life today possible.
3. Only Jesus is the true living water, and only in Him do we find lasting satisfaction and true refreshing. Whoever drinks the water Jesus gives will never thirst again (John 4:14).
Thank You Jesus for giving us reason to celebrate and be glad. Thank You for commanding Your people to celebrate and rejoice. It shows what a joyful, refreshing, fun and big hearted God you are, that You want us Your people to be refreshed and full of joy.