During the seventh month of Israel"s religious calendar three festivals took place. This reflects the importance that God attached to the number seven in the Mosaic economy. Not only was the seventh day special ( Leviticus 23:3) but so were the seventh week ( Leviticus 23:15-22) and the seventh month. [source][source][source]
The Jews celebrated the Feast of Trumpets (Heb. Rosh Hashana) on the first day of this month. The Israelites blew trumpets on the first day of every month, but on this month the trumpets signaled the Feast of Trumpets as well as the beginning of a new month. After the Babylonian captivity the Jewish civil year began on this day. It became a new year"s celebration in Israel"s calendar. We can calculate the Jewish year number at Rosh Hashana by adding3761to the Christian year number. [source][source][source]
The ram"s horns (shophars) that the priests blew on this occasion were quite large and produced "a dull, far-reaching tone." [1] They called the congregation to turn attention freshly to God and to prepare for the other two festivals of the month and the12months ahead. They also signaled God"s working again on behalf of His people. [source][source][source]
A trumpet will sound calling Christians to meet the Lord in the air ( 1 Corinthians 15:52; 1 Thessalonians 4:16-17). It will also assemble the Israelites and herald the Day of the Lord when God will again resume His dealings with His people Israel in Daniel"s seventieth week ( Jeremiah 32:37). Some commentators have felt that this event will provide a prophetic fulfillment of the Feast of Trumpets. [source][source][source]
"God calls his people away from their earthly labors to join the saints in his presence where they may worship him wholeheartedly." [2][source]