This is taken from Saviours Of Islamic Spirit by Shaykh Abul Hasan Ali Nadwi.

On 9th Jamad ul-Ula, 705 A.H., a group of extremist Rafa'iyah mendicants called upon the governor of Syria and demanded that Ibn Taimiyah should be stopped from enforcing the rules of Shari'ah on them. Ibn Taimiyah, on the other hand, insisted that every one would have to govern his conduct accord*ing to the principles laid down in the Scripture and the Tradi*tions, and, whoever tried to transgress these rules, would be opposed by him. The Rafa'iyahs also volunteered to enact certain black arts like walking on fire as a proof of their being on the righteous and divinely approved path. They claimed that their wonder-working was accepted as a mark of piety by the Tartars. Ibn Taimiyah refused their plea and remained firm on his demand with the result that the Rafa`iyahs had to put off the iron rings worn by them. Later on Ibn Taimiyah wrote an exhaustive article delineating the history, beliefs and the practices of the Rafa'iyah order. (Ibn Kathir, Vol. XIV, p. 35)