"And the LORD spake unto Moses, saying, Speak unto the children of Israel, saying, In the seventh month, in the first day of the month, shall ye have a sabbath, a memorial of blowing of trumpets, an holy convocation" (Leviticus 23:23-24).
Today's date is the first day of the Jewish civil year. Its ancient observance was in connection with the "feast of trumpets," described in Leviticus 23:24. "In the seventh month, in the first day of the month, shall ye have a sabbath, a memorial of blowing of trumpets, an holy convocation."
The ancient rabbis taught that God created the world in the first week of the seventh month, Tishri. The first day of that seventh month was considered the anniversary of the beginning of the creation. Today it is called Rosh Hashanah, meaning "Head of the Year." It is still observed among the Jews, although not as in former times.
The blowing of trumpets was not only to celebrate the New Year and to commemorate God's creation, but also to remember Abraham's willingness to sacrifice Isaac (see Genesis 22:1-19). Each trumpet (Hebrew, shofar) was made of a ram's horn and this usage was attributed to God's provision of the ram which Abraham had offered "for a burnt offering in the stead of his son" (Genesis 22:13).
To Christians, however, the blowing of a divine trumpet will have a different significance. "In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed" (I Corinthians 15:52). "For the Lord Himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first: Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air" (I Thessalonians 4:16-17). HMM