“He was sincere, but he was mistaken”

The objection

“He was sincere, but he was mistaken.”

This is the most measured form of the objection, and the most serious. It no longer accuses him ﷺ of imposture: a historian such as W. Montgomery Watt held his sincerity to be established (research file v1, part 4). But sincerity proves good faith, not truth. A man may believe with all his soul that God speaks to him, and be wrong. The classic argument, “liar or truthful”, overlooks a third way: sincere error.

The answer

The starting point: he ﷺ was not lying

The objection starts from a point already won, which is worth recalling. Heraclius, questioning Abu Sufyan, concluded that a man who did not lie to people would not lie about God (Bukhari 7). Umayya ibn Khalaf, his adversary, said: “by God, Muhammad ﷺ does not lie when he speaks” (Bukhari 3632; Ibn Kathir, Mu’jizat, I, 242-243). The Qur’an affirms that his adversaries do not accuse him of lying:

It remains to be seen whether a sincere man could have deceived himself. The Qur’an answers each hypothesis: lying (10:16; 69:44-46), madness (34:46), and going astray, which is sincere error (research file v1, part 4):

This answer the objection will reject: it is the very text in question that asserts it. What is needed, then, are facts that error does not explain. There are four.

An error does not foretell the future

One who is mistaken about the origin of his thoughts knows the future no better than anyone else. Yet what the Prophet ﷺ foretold came to pass:

• the defeated Romans will be victorious “within a few years” (30:2-4): the counter-offensive of Heraclius begins in 622, and peace comes in 628 (research file v1, part 4);
• Abu Lahab and his wife will burn in the Fire (sura 111): Abu Lahab dies an unbeliever some ten years later, when a feigned conversion would have been enough to refute the Qur’an (research file v1, part 4);
• on the eve of Badr, he ﷺ shows on the ground the places where men of Quraysh whom he names will fall, and none of them strays from it (Muslim 1779; Muslim 2873);
• Umayya ibn Khalaf will be killed: he tries to avoid Badr, is drawn into it, and is killed there (Bukhari 3632);
• a fire will come out of the Hijaz and light up the necks of the camels at Bosra (Bukhari 7118): it appears near Medina in 654 AH (1256), nearly four centuries after the collection was written down (Ibn Kathir, Mu’jizat, I, 372-373; research file v1, part 4).

The Bible makes fulfilment the test of a prophet:

“When a prophet speaketh in the name of the LORD, if the thing follow not, nor come to pass, that is the thing which the LORD hath not spoken” (Deuteronomy 18:22).

The prophecies of Muhammad ﷺ pass this test; an error, however sincere, would not.

An error does not reprove the one it misleads

Would a conviction born of himself have taken the side of the blind man against him ﷺ? The Qur’an, for its part, reproves him: “He frowned and turned away, because the blind man came to him” (80:1-2); “May God pardon you! Why did you give them leave?” (9:43); and on the captives of Badr (8:67) (research file v1, part 4).

An error does not keep him waiting

If the revelation were the echo of his desires, it would come when he ﷺ needed it. In the affair of the slander against Aisha, his wife, he remains a month with nothing revealed to him about her (research file v1, part 4), until the verses that clear her come down (24:11).

He ﷺ himself distinguishes his opinion from the revelation

This is the decisive point. Sincere error supposes a man who confuses his thoughts with the voice he believes he hears. He ﷺ keeps them apart. About the pollination of the palm trees, he says: “you know better the affairs of your world” (Muslim 2363; research file v1, part 4). He thus sets apart his opinion on the things of this world, and leaves it to the judgement of those who know more. A man who took his own thoughts for the word of God would not draw that line.

What the objection gets right

Sincerity alone does not prove truth. The objection is right on this point, and that is why the reasoning of Heraclius is not enough on its own: it rules out lying, not error.

He could be mistaken in the affairs of this world. The tradition itself reports it (Muslim 2363). But it is he ﷺ who draws that line, and the hypothesis of error must still explain what it cannot explain: precise prophecies fulfilled, one of them nearly four centuries after it was written down.

Further reading

• The test of the true prophet: His prophecies, from his lifetime to our day.
• The signs drawn from his person ﷺ: The testimony of his person.
• The prophecies fulfilled in his lifetime: Fulfilled in his lifetime.
• A related objection: “The revelation was a fit, or a possession”.
• All the objections: Objections answered.

Sources for this page

• Qur’an: Tanzil text (Uthmani); translation of the meaning by this site.
• Bible: King James Version.
• Heraclius and Abu Sufyan: Bukhari 7.
• Umayya ibn Khalaf: Bukhari 3632.
• The places at Badr: Muslim 1779; Muslim 2873.
• The fire of the Hijaz: Bukhari 7118.
• The pollination of the palm trees: Muslim 2363.
• Ibn Kathir, Mu’jizat al-Nabi ﷺ (extract from al-Bidaya wa-l-Nihaya), ed. al-Sayyid Ibrahim Amin Muhammad, al-Maktaba al-Tawfiqiyya, Cairo, I, 242-243, 372-373.
• Research file “Annonces du Prophète ﷺ”, v1.0, 14 October 2026, part 4.