Tahrif

Taḥrīf (Arabic: تحريف‎‎, "distortion, alteration") is an Arabic term used by Muslims for the alterations which Islamic tradition claims Jews and Christians have made to the revealed books, specifically those that make up the Tawrat (or Torah), Zabur (possibly Psalms) and Injil (or Gospel).

Traditional Muslim scholars, based on Qur'anic and other traditions, maintain that Jews and Christians have changed the word of God.

The theme of tahrif was first characterised in the writings of Ibn Hazm (10th century), who rejected claims of Mosaic authorship and posited that Ezra was the author of the Torah. He also systematically organised the arguments against the authenticity of the Biblical text in the first (Tanakh) and second part (New Testament) of his book: chronological and geographical inaccuracies and contradictions; theological impossibilities (anthropomorphic expressions, stories of fornication and whoredom, and the attributing of sins to prophets), as well as lack of reliable transmission (tawatur) of the text. He explains how the falsification of the Torah could have taken place while there existed only one copy of the Torah kept by the Aaronic priesthood of the Temple in Jerusalem. Ibn Hazm's arguments had a major impact upon Muslim literature and scholars, and the themes which he raised with regard to tahrif and other polemical ideas were modified only slightly by some later authors.

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