"Void Meditation is what is known as "stilling the mind." The benefits of void meditation are the ability to turn off unwanted thoughts and influences at will, being able to control your thoughts instead of your thoughts controlling you (as with the average person), and a sense of inner peace."
Source:
https://satanisgod.org/www.angelfire.com/empire/serpentis666/Satanic_Void_Meditation.html