Nowadays music is considered somewhat neutral, as a pure art or as entertainment, but in the past it was much more embedded in wider life, with functional and symbolic significance.
One big reason for that was that before the rise of recordings, all musical acts were necessarily done in real time by a live human performer. This meant that the music was done for something, for someone, and not (as often now) just happening as background noise.
Because of this intentionality of performance, all aspects of music had purpose and meaning. I was particularly thinking of the significance of musical instruments recently. I think that certain instruments still do retain these symbolisms and resonances, but in a less clearly articulated way.