Why did Ahl al-Sunnah wal-Jama'ah choose the principles by which they excluded those who declared the perpetrator of a major sin to be a disbeliever, and those who said that faith neither increases nor decreases, and others? And on what basis are these principles called the principles of Ahl al-Sunnah wal-Jama'ah? And is one considered an innovator (mubtadi') if he does not consider the Mawlid an innovation and deems it good? And who is the innovator? Is it everyone who contradicts the principles of Ahl al-Sunnah codified in books of creed, or everyone who commits an innovation and is bigoted about it? And to which group is he attributed?

The fundamental principles of Ahl al-Sunnah are those established by evidence from the Qur'an and Sunnah, and upon which Ahl al-Sunnah have reached a consensus. Examples include: faith being both a statement and an action; that the perpetrator of a grave sin is under Allah's will (subject to His decision); the affirmation of Allah's attributes; belief in divine decree (Qadar); that the Qur'an is the uncreated word of Allah; and the affirmation of intercession for sinners. These principles served as a distinguishing mark for Ahl al-Sunnah, and anyone who contradicted them was considered an innovator. The Salaf regarded these as foundational principles of Sunnah to differentiate them from secondary, jurisprudential issues.

Innovations (Bid'ah) vary. Some are polytheistic (shirk-related), like the worship of the dead. Some are belief-based and lead to sinfulness (mufassiqah), like the innovation of the Khawarij. And some are practical, like the innovation of Mawlid (celebrating the Prophet's birthday).

A specific person is not judged as an innovator unless the evidence has reached them, as they might be excused due to ijtihad (independent reasoning), taqlid (following a scholar), or inability.