“If the trumpet does not sound a clear call, who will get ready for battle?” 1 Corinthians 14:8
Watchman on the Wall! In the old days a city would have a wall around it to protect the people from their enemies. They would appoint watchmen to serve as look-outs on the wall. When they would see the enemy approaching, they would blow the trumpet [shofar] to warn the people of coming war.