Izhar al-Haqq (Demonstration of the truth) is a work of Islamic apologetics that broke new ground in the Muslim approach to the Bible and to Christian doctrine. Written by Indian Shia scholar Rahmatullah al-Dihlawi (circa 1817−91), it received the approbation of the Ottoman sultan, Abdülaziz (reigned 1861−76). It was printed in 1867 at the imperial press in Istanbul for distribution among Arabic-speaking Muslims. Rahmatullah based his innovative approach on analysis of European Protestant historical or higher criticism, i.e., on reinterpretations and reformulations of biblical historiography made by European theologians themselves. This was a major departure from the customary defense of Islam made by reference predominantly to Muslim scripture. The book is said to have grown out of arguments put forward by Rahmatullah in his 1854 debate with German missionary Carl Gottlieb Pfander (1803–65) in Aligarh, India. Debate continues among Muslim scholars regarding textual and interpretive portions of the work. This edition includes brief laudatory introductions in Arabic and Ottoman Turkish, and the author himself supplies an important introductory essay. The detailed colophon and the high-quality printing point to the care taken in the production of the book. Presented here are two volumes bound as one.