The Bible tells us so. That is 288 people devoted to the Lord's music. I think that was pretty loud. The proposed Catholic law would have certainly silenced them. This is contradictory to the word of God .
Music is a powerful stimulant to the soul.
The unbeliever goes inside the church to find out what is going on. They look around and realize that they don't have the kind of joy that these Christians do. And they don't know Jesus in the personal way that these Christians seem to. They are curious. In the end, they find out the truth and get saved.