There is a school of Sufis in the East called the Rifai school. The main object of this school is to increase the power of spirit over matter, and such experiments as eating fire, or jumping into the fire, or cutting the body are made in order to get power and control over matter. The secret of the whole phenomenon is that by the power of words they try to tune their body to that pitch of vibration where no fire, no cut, nothing can touch it. Because the vibrations of their body are equal to those of the fire, therefore the fire has no effect.