Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
Dear questioner, thanks so much for your question which reflects your desire to have a clear view of the teachings of Islam. Allah commands the Muslims to refer to the people of knowledge to acquaint themselves with the teachings of Islam as well as all aspects of life.
As for your question, it should be clear that music that is free of un-Islamic and immoral themes and messages is permissible.
In response to your question, Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
I don't believe that music in itself is considered haram (prohibited); it is just like all other forms of entertainment; the haram of it is haram, and the halal (permissible) of it is halal. How can Islam prohibit all forms of music when it is based on balance, and harmony and has a sound nature?
Islam forbids music that contains themes or messages that are profane, immoral, and degrading to the human spirit. So any music that falls into this category shall be considered haram. On the other hand, any music that uplifts the human spirit, and contains noble and ethically sound themes is considered permissible.
Having said this, we must also point out the following:
If a person is addicted to music in such a way that he is distracted by it from fulfilling his important religious duties or other obligations, it shall be considered haram for him to listen to it.
So we cannot say that qawali itself is considered haram, for it contains noble themes of praising Allah and the Prophet (peace and blessings be upon him). However, I must also point out that sometimes they border on excessive veneration in praising the Prophet (peace and blessings be upon him); so we must be careful of such tendencies, but this should not prevent us from benefiting from those parts of qawali that are sound and uplifting.
Now coming to the final point, whether we are allowed to listen to Western music, let me state: We are allowed to listen to any type of music that fulfills the following criteria:
1. Its message is noble and ethically sound in Islam;
2. It is not addictive or distracting from one's important duties or obligations;
3. It is not over-done; in other words, one must never indulge in it except as an occasional outlet, for a believer has other important things in life that he/she must focus on, so do not use it except as an occasional outlet or diversion. As reported in tradition, 'You should have occasional outlets!'