for if that is truly impossible, no one can be certain that all the manuscripts agree with one another to the point that someone could testify they are identical in wording and meaning. Indeed, the likelihood of their being tampered with is far greater than the likelihood of anyone being able to certify their complete agreement.

For this very reason no one can alter the Qur’an: it is safeguarded in people’s hearts and transmitted through uninterrupted mass transmission, even though we do not claim that every written muṣḥaf is identical. Some copies may contain scribal errors that the memorizers of the Qur’an detect at once, without needing to consult another muṣḥaf.

By contrast, none of those earlier scriptures is memorized by a community whose collective transmission could serve as a standard against which the manuscripts might be checked. While prophets—peace be upon them—were still among them, the prophets themselves were the ultimate reference whenever parts of the books were altered. Once prophethood ceased among them, corruption spread swiftly.

Thus, many Christians replaced large portions of the religion of Christ—peace be upon him—only a short time after he was raised up, and they continued to change it little by little. Yet a group among them remained steadfast upon the true religion until Allah sent Muhammad—may Allah bless him and grant him peace.

A small remnant of those who adhered to the true faith survived, as is confirmed in the authentic hadith recorded by Muslim in his Ṣaḥīḥ, on the authority of ʿIyāḍ ibn Ḥimār al-Mujāshiʿī, that the Prophet said: