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.

Numbers 29:1-6

Offerings for the Feast of Trumpets

1“On the first day of the seventh month you shall have a holy convocation. You shall not do any ordinary work. cIt is a day for you to blow the trumpets, 2and you shall offer a burnt offering, for a pleasing aroma to the Lord: one bull from the herd, one ram, seven male lambs a year old without blemish; 3also their grain offering of fine flour mixed with oil, three tenths of an ephah
An  ephah was about 3/5 bushel or 22 liters
for the bull, two tenths for the ram,
4and one tenth for each of the seven lambs; 5with eone male goat for a sin offering, to make atonement for you; 6besides fthe burnt offering of the new moon, and its grain offering, and gthe regular burnt offering and its grain offering, and their drink offering, according to the rule for them, for a pleasing aroma, a food offering to the Lord.

Nehemiah 8:2

2So Ezra the priest hbrought the Law before the assembly, both men and women and all who could understand what they heard, ion the first day of the seventh month.
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