1 Chronicles 5:13-14 It came even to pass, as the trumpeters and singers were as one, to make one sound to be heard in praising and thanking the Lord; and when they lifted up their voice with trumpets and cymbals and instruments of music, and praised the Lord, saying, For he is good; and his mercy endureth forever; that then the house was filled with a cloud, even the house of the Lord; so that the priests could not stand by reason of the cloud: for the glory of the Lord had filled the house of God.
When the priests and Levites brought the Ark of the Covenant into the Holy of Holies inside the newly finished Temple, the musical instruments and the vocal singers made one sound of praise and thanksgiving to the Lord. The response to God coming to live among His people was harmonious and beautiful, but also loud. The event was certainly awe-inspiring and powerful, as humans are able to make glorious sounds of praise with voices and instruments.
But even the awesome response of the people was overshadowed by the cloud of glory that filled the temple. The glory of God is so overwhelming that the priests could not stand before the glory. They fell in humble worship. This is actually what happens to us when we experience baptism and conversion. We still kneel in Holy Communion when we are faced with such glorious love and grace. We fall in abject adoration when we experience God. Look what happens to the angels in heaven when one sinner repents: “There is more joy among the angels in heaven over one sinner who repents.” Inwardly, we cannot stand when the Lord reveals His glory in mundane, visible things like Word and Sacrament. That’s why we go to church.