'Blow the Trumpet' in the Bible

Have seven priests carry seven ram’s-horn trumpets in front of the ark. But on the seventh day, march around the city seven times, while the priests blow the trumpets.

However, if the watchman sees the sword coming but doesn’t blow the trumpet, so that the people aren’t warned, and the sword comes and takes away their lives, then they have been taken away because of their iniquity, but I will hold the watchman accountable for their blood.