The piercing blast of the Shofar has made generations of Hebrew peoples tremble.  Fashioned from a ram's horn, this simple trumpet produced a tone likened to a loud shout.  The signal blast of the Shofar was blown to assemble the congregation, as an announcement of joy, but also, it was an alarm of imminent war, and the trumpets of Revelation are an alarm of imminent war that shall sound forth in the future announcing the return of Jesus Christ to this earth.