Before giving the main answer an introduction is necessary. Sunni resources such as Tanzīh al-Anbiyā’ of Fakhr Rāzī[1] have discussed infallibility in four segments:

1. Infallibility in relation to the beliefs of the Prophet. There is a consensus among all Islamic sects that the Prophet was immune of liability to error in his beliefs.

2. Infallibility in relation to the legal rulings and divine demands. About this segment there is also a general agreement among Islamic sects neither accidentally, nor deliberately makes any mistakes in this regard. The reason behind this is the fact that should the Prophet be liable to error, he cannot be trusted because we must be sure that his words are the words of God Almighty in order to follow his demands assuredly.

3. Infallibility in relation to his verdicts. Here we also have a consensus that he doesn’t make any deliberate mistakes. However, unintended mistakes are subject to debate and disagreed upon.

4. Infallibility in relation to his actions and different states, which encompasses matters other than the reception and conveyance of revelation. There are five opinions regarding this segment:

A. Ḥashwīyyah Ash‘arites believe that major and minor sins were possible for the Prophet except for infidelity and falsehood - meaning that they do not consider infalliblity to be necessary.

B. Most of the Mu‘tazilites believe major sins not to be possible for the Prophet to commit, but minor sins are possible if they don’t cause hatred towards the Prophet.

Abu Ali Jabā’ī says: Every sin committed on accident is permissible.

Nizām believes that no sin is possible but accidents are possible.

C. The Shi’ite school of thought doesn’t accept any sins or mistakes, be it intentional or unintentional, from the Prophet and Imams.

After mentioning the four segments listed above, Fakhr Rāzī lists fifteen reasons regarding the immunity of the Prophet – some merely intellectual reasoning and some accommodated with verses of the Quran – which we will not mention and leave to refer you to their sources.[2]

Therefore, according to the beliefs of the Sunni school of thought, derived from their authentic resources, Sunnis do not believe in the infallibility of the Prophet regarding issues other than revelation, thus there is no reason to state their arguments in proving it. They simply believe in the infallibility of the Prophet regarding the reception and conveyance of revelation and their reason as to why he is infallible is that we must be able to trust what the Prophet says and that he has received and conveyed the message of God correctly.[3]

However, a group of Sunnis believe that the Prophet is definitely infallible before major and minor sins that cause hatred towards him – both before and after becoming prophet.[4]

Shi’ism is the only Islamic sect that extends the infallibility of the Prophet (S.A.) to the point where it covers every aspect of his life.

For more explanation please refer to the following books:

1. Aḍwā’ al-Bayān, Muhammad al-Amin al-Shanqīṭī, Vol. 4, p. 188.

2. Sharḥ Mawāqif, Qāḍī ‘Aḍud Ījī.