Leviticus 23:24

24Speak to the people of Israel, saying, In athe seventh month, on the first day of the month, you shall observe a day of solemn rest, ba memorial proclaimed with blast of trumpets, a holy convocation.

Deuteronomy 16:16

16 cThree times a year all your males shall appear before the Lord your God at the place that he will choose: at the Feast of Unleavened Bread, at the Feast of Weeks, and at the Feast of Booths. dThey shall not appear before the Lord empty-handed.
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