Izhar ul-Haqq or Izhar al-Haq (Arabic: إظهار الحق) is Rahmatullah Kairanawi's magnum opus. Originally written in Arabic in 1864, this six-volume book was later translated (or summarized) into English, Turkish and Urdu.
Christine Schirrmacher describes the book saying:
| “ | 'The Demonstration of the Truth' (izhâr al-haqq) served as a summary of all possible charges against Christianity and was therefore used after al-Kairânawî's death as a sort of encyclopaedia since al-Kairânawî extended the material of former polemicists like 'Ali Tabarî, Ibn Hazm or Ibn Taymiyya to a great extent. | ” |