Excerpts from Hazrat Inayat Khan's The Mysticism of Sound & Music:

"Many in the world take music as a source of amusement, a pastime; to many music is an art, and a musician an entertainer. Yet no one has lived in this world, has thought and felt, who has not considered music as the most sacred of all arts. For the fact is that, what the art of painting cannot clearly suggest, poetry explains in words, but that, which even the poet finds difficult to express in poetry, is expressed in music.

By this I do not only say that music is superior to painting and poetry: in fact music excels religion, for music raises the soul of man even higher than the so-called external form of religion. But it must not be understood that music can take the place of religion, for every soul is not necessarily tuned to that pitch where it can really benefit from music, nor is every music necessarily so high that it will exhat a person who hears it more than religion will do. However, those who follow the path of the inner cult, music is most essential for their spirutual development. The reason is that the soul who is seeking for truth is in search of the formless God. Art, no doubt, is most elevating, but it contains form; poetry has words, names suggestive of forms; it is music which has beauty, power, charm, and at the same time can raise the soul beyond form."

"Every soul differs in its choice in life, in its choice of the path it should follow. This is owing to the difference of the minds, for soulds, in their essence, do not differ. Therefore, whatever means be chosen to bring the different minds of people together, there cannot be a better means of harmonizing them than music. It would not be an exaggeration if I said that music alone can be a means by which the soul of races, nations and families, which are today so far apart, may one day be united. The musician's lesson in life is therefore a great one. Music is not expressed through language, but through beauty of rythm and tone which reach far beyond language. The more the musician is conscious of his mission in life, the greater service he can render to humanity.

As to the law of music which exists in different nations, there are of course different methods, but in the conception of beauty there is no difference. The differences come when the music is man-made; there is no difference in the soul-made music. Suppose a man comes from the far East, the extreme North, South, or West; wherever he sees the beauty of nature he cannot help admiring and loving it. So it is with the music lover. From whatever country he comes, and whatever music he hears, if the music has a soul, and if he seeks for the soul in music, he will appreciate and admire all music."