Abd Allah ibn Sa'd ibn Abi al-Sarh (Arabic: عبد الله ابن سعد ابن أبي السرح, romanized: ʿAbd Allāh ibn Saʿd ibn Abī al-Sarḥ) was an Arab administrator, scribe, and military commander, who was an early convert to Islam . He was a scriber of the Quran (كاتب الوحي) and governor of Upper Egypt for the Muslim caliphate during the reign of ʿUthmān (644–656). He was also the co-founder (with the future caliph Muʿāwiyah I) of the Islamic navy which seized Cyprus (647–649) and defeated a Byzantine fleet off Alexandria in 652.

al-Sarh came from the Banu Amir ibn Lu'ayy clan of the Quraish tribe and was an adopted brother of the caliph Uthman. After converting to Islam, he became a Companion of Muhammad and, later, a Scriber.

During his time as a scribe, Muhammad would dictate to him a revelation to be written down, as he did with other scribes. Some later Islamic chronicles report that he subsequently left Islam and returned to Mecca, expressing uncertainty about the nature of revelation. Abi Saleh, narrated from Ibn Abbas, recorded that:

"the Messenger of Allah invited him so that he could write him the revelation, so when the verse 23:12 ("And certainly did We create man from an extract of clay") was revealed, the Prophet called Ibn Abi al-Sarh, and dictated it to him and when the Prophet reached the end of 23:14 ("...Thus, We formed him into a new creation") Abdullâh said in amazement ("فتبارک اللّٰہ احسن الخالقین So blessed be Allah, the Best of creators!"). The Prophet said:" Write these words too (i.e., فتبارک اللّٰہ احسن الخالقین "So blessed be Allah, the Best of creators!"), as these words have also been revealed to me."

Al-Sarh claimed that this made him doubt, and he is recorded as having said: "If Muhammad is truthful then I (am also a prophet, as I also) received the revelation, and if Muhammad lied, then I say of the like of his speech (i.e. neither his speech nor mine speech are the words of Allah)". Al-Sarh further tested his doubts, with Muslim historians Waqidi, Ibn al-Athir and Tabari writing that Muhammad dictated him: "عليم حکيم" i.e. "Allah is All Knowing All-Wise", which al-Sarh deliberately wrote in the opposite order, i.e. "حکيم عليم, All-Wise All Knowing". He then recited it to Muhammad, who did not detect any changes. Waqidi wrote that "(Ibn Abi Sarh said): Muhammad didn't know what he dictated, and I wrote (in Quran) whatever I wished. And what I wrote, it was a revelation upon me, just like it was a revelation upon Muhammad."

Certain narrations attributed to Ibn ʿAbbas and transmitted through Muhammad ibn al‑Saʾib al‑Kalbi (also known as Abū al‑Nadr al‑Kūfī) are considered extremely weak. Al-Qurṭubī mentions in Tafsīr (7/40) that “it was narrated by al‑Kalbi from Ibn ʿAbbas,” while al-Munawī records in Al-Fath al-Samāwī (2/612) that “it was narrated by al-Wāhidī from al‑Kalbi, from Abū Ṣāliḥ, from Ibn ʿAbbas.” The chain of transmission is criticized by scholars and is considered very weak due to al‑Kalbi’s reputation as a fabricator of hadith. Sufyān al-Thawrī reportedly stated, “Al-Kalbi said to me: Everything I narrate to you from Abū Ṣāliḥ is a lie,” and Ahmad ibn Zuhayr reported that upon asking Ahmad ibn Hanbal whether it was permissible to consult al-Kalbi’s tafsir, he replied, “No.” Classical scholars, including al-Taymī, al-Jawzajānī, and al-Hākim, declared al-Kalbi a liar, and his narrations are generally not accepted in serious tafsir or hadith scholarship.

Al-Ṭabarī, in his Tafsīr (11/533–534), narrated that the verse “And who says, ‘I will bring down [revelation] like that which Allah has sent down’” was revealed concerning ʿAbd Allāh ibn Saʿd ibn Abī Sarḥ, who used to write for the Prophet Muhammad (peace be upon him). When the Prophet dictated “Mighty and Wise,” he would write “Forgiving and Merciful,” thus altering the wording. Ibn Saʿd later apostatized, joined Quraysh, and claimed to them that he had intentionally altered the revelation, but he returned to Islam before the conquest of Mecca. Al-Ṭabarī transmitted this report through multiple chains of narration, including one via Ḥajjāj ibn Arṭāʾah from Ibn Jurayj from ʿIkrimah, and another via Asbat from Al-Suddī (Ismāʿīl ibn ʿAbd al-Raḥmān al-Qurashī al-Suddī al-Kabīr, a Tabiʿī). Both chains are considered weak: the first is criticized for being mursal (broken) and for including narrators like Ḥajjāj ibn Arṭāʾah and Ibn Jurayj, who were known to practice tadlīs (concealing weaknesses in narration) and to transmit using an ambiguous mode of reporting (‘an‘ana). The second chain through Al-Suddī is also weak because it is mursal, missing the companion link, and thus does not meet the standard criteria of authenticity.

Although al-Sarh was noted to have left Islam before later returning, the authenticity of the report claiming Muhammad had fabricated revelations has been graded as disconnected and fabricated (Mawḍūʻ) by the hadith scholars. The report was narrated by Muhammad bin al-Sa'ib al-Kalbi from Abi Saleh, who attributed it to Ibn Abbas. Al-Kalbi was unanimously deemed weak in hadith, labelled a liar and a fabricator. He was noted to be forgetful, shunned for narrating multiple fabrications, and regarded as one of the great liars in Kufa.