נחמיה, פרק י״ב, פסוק ל״ה

The dedication of the wall of Jerusalem was a grand celebration, marked by loud sounds of joy and a large procession. Leading this festive march were the priestly families, who were specifically entrusted with sounding the trumpets. At the very front of the crowd walked Zechariah, guiding the people forward while blowing the trumpets [ביאור שטיינזלץ, מצודת דוד].

The role of the priests and their trumpets at this event was not just to provide music for the occasion. Their participation was directly tied to a Torah commandment that requires priests to blow trumpets during the bringing of peace offerings. On this day, thanksgiving offerings were brought alongside those peace offerings. Because of these sacrifices, and because the completion of the wall was an occasion of such immense happiness, the priests accompanied the entire dedication ceremony with the continuous sound of their trumpets [רלב״ג].