trumpet: a signaling horn blown to give one loud, unmistakable order, and the blast it makes
In the Bible a trumpet is not an instrument for making music. It is an instrument for making a signal. Its whole job is to cut through noise and distance with a blast nobody can mistake, so that everyone in earshot knows at once what is happening and what to do.
That is why the New Testament reaches for it at the loudest moments in the story:
- a battle signal that has to be clear or no one will arm themselves
- the terrifying sound that shook the mountain when God spoke to Israel
- the summons that gathers God's scattered people from the four winds
- the blast that wakes the dead and changes the living in an instant
- the seven blasts in John's vision, each one loosing a fresh judgment on the earth
Twice the word simply measures volume and clarity. John hears a voice behind him that sounds like a trumpet, meaning it is loud, piercing, and impossible to ignore.
Sometimes the word points to the instrument itself, the thing an angel holds and gets ready to blow, and sometimes it stands for the blast that instrument makes, much as English can say "the last trumpet" and mean the final signal rather than the horn. The act of blowing it has a word of its own (σαλπίζω), which often stands right beside this one.