Even sympathetic medieval readers of the Qur’an lacked the Arabic to read it directly

Evidence

Richard Fitzralph was equally individual but very different in his approach. Working over Ketton’s paraphrased Qur’an with a scholarly care and scrupulous attention to the letter which he was unable to give to the Arabic, he formed an idea of the Islamic Christ as ‘a pure and blessed one’, and, together with this, some very odd notions indeed. — Norman Daniel, Islam and the West, 960