Other recent posts of the words of Hazrat Inayat Khan on music may be found here, here, here and here.

Why is music called the divine art and all other arts are not called so? Certainly we may see God in all arts and all sciences, but in music alone we see God free from all form and thought. In every other art there is idolatry. Every thought, every word has its form; sound alone is free from form. Every word of poetry forms a picture in your mind; sound alone does not make any object appear before you. All would rather hear music than a speech. By sound the world was created. In Vedanta it is called Nada Brahma, Sound-God. 

A Persian poet says, “They say that the angels sang to the soul to make it become man, but really the soul was sound.” The poets have said that by singing the angels induced the soul to enter the human body. The soul that has always been free is unwilling to enter the body. Really, before its incarnation the soul is sound. It is for this reason that we love sound. The breath, the speech, the step, all have rhythm. Religions have all made music part of their worship. The Sufi especially loves music, calling it Ghiza-i-ruh, food of the soul.