"Thus saith the Lord God, the Mighty One [Heb. abiyr] of Israel: Behold I say unto you, my servant Edward, that you are blessed, and your sins are forgiven you, and you are called to preach my gospel as with the voice of a trump." -- D&C 36:1.
Thus spake the Lord to Edward Partridge, a faithful early Latter-day Saint, calling him to missionary work, echoing the words to Oliver Cowdery earlier that same year of 1830.
Isaiah, the poet-prophet, may have first recorded this divine metaphor:
lift up thy voice
like a trumpet."
-- Isaiah 58:1
When I think of a trumpet, I think bold, compelling, clear ... and beautiful. Such should be our witness.