Time and space are the very music of God's harp, for each moment in time is empty of other moments, and each part of space is empty of other parts, so that we will not have to hear too much at once. That is why there are seasons.
To listen to music or to sing a chant is to do something that has no practical purpose; it is just celebration and praise; it is just tasting the joy and beauty of life, the glory of God. Listening to it, even in the midst of a very purposeful day, reminds us to add the other dimension to our experience, the dimension of meaning, that makes it all worthwhile.