From the excellent book (published by al-ibaanah) The Rules and Etiquettes of Ruqya, by Shaikh Saalih Aalush-Shaikh p.37-39
“When Shaikh Abdullah Al-Qar’aawee1 came to our region, many people were suffering from illnesses; they were bed-ridden and couldn’t get up. And what was this due to? It was due to the Jinn and so on and so forth. They would go out and come across the Jinn at night in trees and upon the roads and so on, and the devils would take over them. This is because they were ignorant. They didn’t have any understanding of Tawheed.
So when he (i.e. Shaikh Al-Qar’aawee) came and spread Tawheed, not ruqyah or anything else, may Allah bless you, all of these things came to an end. All of these (possessions and illnesses) came to an end once Tawheed and knowledge spread. When Tawheed and knowledge spread, these things go away and come to an end. And when ignorance becomes widespread, sorcerers, soothsayers, devils and so on increase and cooperate with one another.
So I advised him to do as the good doers in the past did, which was to call to Tawheed and wage war against shirk and false superstitions such that the devils left them and they had no need for people to perform ruqyah on them from devils, sorcerers or anyone else….”
Translator’s Note:Shaikh Abdullah Al-Qar’aawee was born in 1315H in Saudi Arabia where he played a great role in reviving the call to Islaam, particularly in its southern regions, making Saamitah the center of his efforts. He studied under such Scholars as Shaikh Muhammad bin Ibtaheem, the former muftee of Saudi Arabia, and produced students of his own such as Shaikh Haafidh Al-Hakamee. He passed away in 1389H, may Allah have mercy on him.