Ikhwân al-Safâ (The Brethren of Purity, A.D. X. C.), who are known as the first humanist community in the history of Islamic thought, considered relation between philosopy and religion within their major work as called Rasâ’il Ikhwân al-Safâ. Ebû Hayyân al-Tevhidî, in a work as called al-İmta’ ve al-Müânese, relates that  Ikhwân es-Safâ attempted to reconcile philosophy wiht religion in their work and their attempts are criticised by al-Sicistanî and al-Harirî. In this article, we aim to discuss, depending on al-Tevhidî’s rumours, al-Harirî’s and al-Sicistanî’s critics about the views of Ikhwân al-Safâ which reconciling philosophy whit religion and Makdisî’s replies to them.