'Festival' in the Bible

"It will come about that all of the survivors of the nations who came against Jerusalem will come there from year to year to worship the King, the LORD of the Heavenly Armies, and to observe the Festival of Tents.

If the people of Egypt do not come to Jerusalem to take part, they will have no annual Nile overflow. A plague will come from the LORD to strike the nations who do not come to observe the Festival of Tents.

This will be the punishment for Egypt and all nations who do not come to observe the Festival of Tents."