Muslims unanimously agree that the Holy Qur'an is unaltered and undistorted. Theologians and experts in exegetical sciences have cited some verses and narrations to reject any kind of possible omission from the Holy Qur'an. According to mainstream Shi'a scholars, Mufassirun(commentators), jurists, and experts in Qur'anic exegetical sciences, the present Qur'an, with all its orders and structures, was written and documented during the life of the Holy Prophet (s). Some Sunni theologians, like Khayyat Mu'tazili and Abu 'Ali al-Juba'i have accused Shi'a of believing in Tahrif (distortion) of the Holy Qur'an. After the publication of Fasl al-Khitab by Muhaddith Nuri, this accusation entered a new phase. In many works, Shi'a scholars have criticized the book of Muhaddith Nuri. Hadith of Thaqalayn, narrations promising rewards for recitation of each Sura, accountability of present Qur'an in different theological and jurisprudential disputes, and challenge for similar verses, are among the most substantial arguments for the fact that the Holy Qur'an is undistorted.