In the risalat on music, Imam Ahmed ul Mastoor, discusses the importance of harmony and right combination which are sine qua non for any type of music. Music has a powerful effect on the human soul. It can create feelings of happiness, sadness, hatred, love; it can motivate, incite, provoke or calm.. All this is done by deft changes in the rhythm and cadence. The skill of music was developed by Hokama (men of wisdom) to help them in their tasks. They produced different tunes for different purposes; tunes which melt the hearts of people and make them repent; tunes used by commanders to motivate and embolden their armies; tunes which are used in infirmaries in the early mornings to soothe and alleviate the suffering of the sick; tunes to console the bereaved and tunes to lighten the burden of laborers. Music has an effect on animals too as travelers use it to prod animals carrying heavy loads.
Further in the Risalat, the ImamSA classifies sounds into two types: living and non-living. Non-living sounds are further divided into two categories: natural and instrumental. The sounds created by rocks, minerals, wind and thunder are examples of natural sounds, while the sounds created by man-made instruments are examples of the latter. Living sounds are further classified into two types: meaningful and non-meaningful. Non meaningful are those sounds which are produced by animals, while meaningful sounds are those produced by humans. These meaningful sounds are further divided into two types: conveying meaning (linguistic) and not conveying meaning (non-linguistic). The sound of laughter, weeping and crying are examples of the latter and the sound of words conveying meaning is the example of the former.
The ImamSA explains in detail how sound is created, and how air carries the sound and conveys it to the recipients, without allowing any distortion. The ImamSA elaborates on the sounds of nature like, wind, water, thunder etc. and how animals produce their sounds using their vocal organs, whereas animals without vocal organs like insects produce sound through vibrations.
The ImamSA embellishes the risalat with an interesting debate between the two prominent sense organs: eyes and ears. Some say that eyes are greater than ears because eyes are like the day and light and ears are like night and darkness. Others reply that ears are more important than eyes as eyes have to go in search of their stimuli (sights), whereas ears do not have to search for their stimuli (sounds); in fact sounds are carried towards the ears. Further, the eyes can see only what is in front of them in a straight line, whereas ears can hear the sounds coming from any direction. Sights are visible and physical whereas sounds are intangible and ethereal. The eyes convey to the mind only what is immediate and present; whereas the ears convey to the heart what is present as well as that which is past and not immediate.
Explaining how music is created, the ImamSA elaborates that it is made up of a combination of tunes. Tunes are the combination of melodies or rhythms. Rhythm is created by beats. The alternation of movement and pause is the foundation of music. This is similar to language which is the combination of sentences, which are the combination of words, which in turn are the combination of letters. Rhythmic movement is the basis of all music. When the rhythm is harmonious the music is pleasant.
Music has the power to stir souls and move hearts. It was originally discovered and used for spiritual purposes; to bring people closer to the creator. But, when people started using it for carnal pleasures, the use of music was forbidden, and was allowed only for the sake of proclamations on occasions like marriages and battles.