Leviticus 23:23

"And Jehovah spake unto Moses saying, Speak unto the children of Israel, saying, In the seventh month, on the first day of the month, shall be a solemn rest unto you, a memorial of blowing of trumpets, a holy convocation. Ye shall do no servile work; and ye shall offer an offering made by fire unto Jehovah."

Perhaps one of the great reasons for celebrating a feast of trumpets on the first day of the seventh month was to usher in the Day of Atonement and the Festival of Tabernacles a short time later. Also, this was the Jewish New Year, the ROSH HASHANAH still observed by the Jews. To understand this, one must remember that the Jews had at least two calendars: (1) that of the religious year; and (2) that of the year. This month was called Tishri by the Jews, but an older name is given to it in 1 Kings 8:2, where it is called Ethanim.

Many scholars have pointed out that the long interval between Pentecost and the feast of Trumpets signaling the arrival of the Harvest Festival (Tabernacles) corresponds to the age of the Church from Pentecost to the Final Judgment.[24] This seems reasonable enough. The church's age will surely end with the "sound of the trumpet" so often mentioned in the N.T. in connection with the Second Advent, and that the harvest festival immediately afterward suggests the harvesting of God's people from the earth is logical enough. Christ himself used the harvest metaphor, and it recurs repeatedly in the Book of Revelation.

There are divided opinions about what kind of trumpet was used. The ram's horn seems to be the most ancient device used for this, but later trumpets were long instruments fashioned of metal. We found no Biblical clarification of the question. The Hebrew word here means simply "loud blasts."[25] Here is "the first mention of the festival of trumpets" in the Bible.[26] It was upon this occasion (first day of seventh month) that Ezra read the law publicly (Nehemiah 8:2). The numerology of the Jews laid stress upon the sacred number seven, and it was appropriate that the seventh month in which occurred both the Day of Atonement and the Feast of Tabernacles should be ushered in ceremonially by the Feast of Trumpets.