The great work of life is not to save the world but to attain God Realization which, by being in the process of doing so, you have a tremendously powerful and positive effect on the world condition and consciousness.
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.