At-Ṭabarī relates that he was known as Abū ʿAbd Allah Fayrūz ad-Daylamī, a descendant of the Persians who had been sent by Khusraw to Yemen, where they conquered it and expelled the Abyssinians. According to ʿAbd al-Munʿim, they later traced their lineage to the descendants of Ḍabbah, claiming:
أصابنا سباء في الجاهلية
“We were taken captive in pre-Islamic times.” At-Ṭabarī, Al-Muntakhab min Dhayl al-Mudhayyal, p. 47.
However, ʿAbd al-Munʿim was mistaken in this assertion. The true account is as follows. Ḍabbah ibn Udd had three sons. One of them assaulted and killed another descendant of Ḍabbah. His father sought to exact retaliation against him, so he fled and settled in the mountains of Daylam. There, he fathered several children, and from him descended the family of Fayrūz. His descendants claim to this day that they possess his saddle and utensils.
Fayrūz is the one who killed al-ʿAnsī, namely al-Aswad ibn Kaʿb al-Kadhdhāb (the Liar), who claimed prophethood in Yemen during the lifetime of the Messenger of Allah . Al-Aswad had misled many people and posed a grave danger to the unity and integrity of the Muslim community. Concerning this event, the Messenger of Allah said:
قتله الرجل الصالح فيروز بن الديلمي
“He was killed by the virtuous man Fayrūz ad-Daylamī.” At-Ṭabarī, same biography.
It has been reported that Fayrūz killed al-Aswad while he was lying in his bed. A report from Ibn ʿUmar states:
أتى الخبر النبي من السماء الليلة التي قتل فيها العنسي ليبشرنا فقال قتل العنسي البارحة قتله رجل مبارك من أهل بيت مباركين قيل ومن هو قال فيروز فاز فيروز
“News reached the Prophet from the heavens on the very same night that al-ʿAnsī was killed, and he came out to give us the glad tidings. He said: ‘Al-ʿAnsī was killed last night, killed by a blessed man from a blessed household.’ He was asked: ‘Who is he?’ He replied: ‘Fayrūz! Fayrūz has been victorious!’” At-Ṭabarī, Tārīkh ar-Rusul wa-l-Mulūk, account of al-Aswad al-ʿAnsī.
This incident demonstrates the divine support granted to the Messenger of Allah and the virtue of Fayrūz ad-Daylamī, who risked his life in order to protect the religion from falsehood and deception. Fayrūz was later blessed with a son named ʿAbd Allah, who became one of the senior scholars among the Successors (at-Tābiʿūn). He was known for his reliability, knowledge, and adherence to the Sunnah. Shaykh Ṣāliḥ ibn Fawzān ibn ʿAbd Allah al-Fawzān said:
“ʿAbd Allah was the son of Fayrūz ad-Daylamī, a trustworthy senior scholar from among the Successors. His father, Fayrūz, was the one who killed al-Aswad al-ʿAnsī, the Liar.”
This statement highlights the lasting scholarly legacy of Fayrūz through his son and confirms his esteemed position among the early Muslims.
At-Ṭabarī’s biographical text places his death during the caliphate of ʿUthmān.
His life remains a powerful example of sincerity, courage, loyalty to the Messenger , and readiness to defend the truth. Through his decisive action against a false claimant to prophethood, he played a crucial role in safeguarding the purity of Islam at a critical moment in its early history.
His story also reflects the diverse ethnic and cultural backgrounds of the early Muslim community, in which faith, righteousness, and service to Islam were the true measures of honour and rank.
References
al-Khaṭīb al-Baghdādī, Tārīkh Baghdād, vol. 5, p. 379; Ibn Saʿd, Aṭ-Ṭabaqāt al-Kubrā, vol. 5, pp. 528–530; Ibn Ḥajar al-ʿAsqalānī, Al-Iṣābah fī Tamyīz aṣ-Ṣaḥābah, vol. 6, pp. 489–491; Aḥmad ibn Ḥanbal, Al-Musnad, vol. 4, pp. 404–406.
Muḥammad ibn Jarīr at-Ṭabarī, Al-Muntakhab min Dhayl al-Mudhayyal min Tārīkh aṣ-Ṣaḥābah wa-t-Tābiʿīn, biography of Fayrūz, p. 47 in the electronic text.
Muḥammad ibn Jarīr at-Ṭabarī, Tārīkh ar-Rusul wa-l-Mulūk, account of al-Aswad al-ʿAnsī vol. 3, pp. 247–250
Ṣāliḥ ibn Fawzān ibn ʿAbd Allah al-Fawzān, Itḥāf al-Qārī bi-t-Taʿlīqāt ʿalā Sharḥ as-Sunnah, vol. 1, p. 214.
