After his capture, Piruz was given as a slave to al-Mughira ibn Shu'ba. In addition to his military skills, Piruz was apparently a skilled carpenter and artisan. According to one report he was involved in the design of a vertical-axis windmill. His master allowed him to live in his own household in the Islamic capital of Medina. According to a SunniSahih Bukhari hadith, which recounts the assassination and Umar's last days in detail, the companion Amr ibn Maymun described Nahavandi as a "non-Arab infidel". In the same hadith, Umar also describes Nahavandi as a non-Muslim: "All the Praises are for Allah Who has not caused me to die at the hand of a man who claims himself to be a Muslim." Al-Tabari described Nahavandi as a Christian. Nahavandi is referred to with the epithetal-Majusi, indicating Zoroastrian beliefs; however, this is likely a pejorative use because of his assassination of Umar.
Assassination of Umar and death
The motive for Nahavandi's murder of Umar has been reported as the latter's refusal to accept Nahavandi's request that al-Mughira be made to tax him less than the two dirhamsa day he was presently taking. In response to the rejection, Nahavandi replied back to Umar with a threat. Sunni tradition has that the next day, in the Hijri year 23, whilst Umar had just begun leading the Fajr prayer in Al-Masjid an-Nabawi, Pirouz had hidden the dagger in his robe, the grip of which was in the middle, and hid himself in a corner of the mosque. Shortly after Umar had begun the prayer, Pirūz leapt upon him and stabbed him six times, this was five times in the stomach and once in the navel, which proved fatal days later. After attacking Umar, Nahavandi stabbed more people, who were trying to subdue him, killing six or nine of them as he tried to flee. When cornered, Nahavandi committed suicide. Shia tradition has reported that Nahavandi killed only Umar and following the assassination Ali provided support and advice to Piruz and, through a miracle, transported him to Kashan, where he safely lived out the rest of his days among fellow adherents of Ali.
Tomb
Pirūz Nahavandi's "revered" tomb is located on the road from Kashan to Fins, constructed in an eleventh-century distinctive Persian-Khwarezmian dynastic architectural style, consisting of a courtyard, porch and conical dome decorated with turquoise coloured tiles, and painted ceilings. The original date of its construction is unknown, but in second half of fourteenth century it was fully restored and a new tombstone was placed over his grave."
Veneration by Shias
Among the Shia, for the act of killing Umar, Nahavandi acquired the honorific title of Baba Shujauddin. The day of Umar's assassination, and the glorification of Nahavandi, is still celebrated in remote Iranian villages and was previously celebrated in major Iranian cities until the protests of Arab countries resulted in its banning there by the authorities. The celebration is known as jashn-e Omar koshi. In 2010, controversy was caused when the International Union for Muslim Scholars called for Nahavandi's tomb to be destroyed—a request which was not well received by some Iranians, having been perceived as a specifically anti-Iranian act. Al-Azhar University also demanded the Iranian government demolish the shrine; the issue caused the cancellation of diplomatic relations between the university and the Iranian government. These requests were made because the shrine is considered to be "offensive and un-Islamic" by mainstream Sunni scholars. Due to this Sunni pressure, it was reported that the Iranian government shut down the shrine in 2010. It is currently used as the local policehead office.
