It is narrated from Sayyiduna Abu Wa'il (may Allah be pleased with him) that Sayyiduna Khalid bin al-Walid (may Allah be pleased with him) wrote a letter to the people of Persia inviting them to Islam: "In the name of Allah, the Most Gracious, the Most Merciful. From Khalid bin al-Walid to Rustam, Mihran and the chiefs of Persia. Peace be upon whoever follows the guidance. To proceed: We invite you to Islam. If you refuse, then pay the jizyah with your own hands while you are subdued; and if you do not accept this either, then with me are people who love being killed in the path of Allah just as the Persians love wine. Peace." There is disagreement about the time of the death of Khalid bin al-Walid (may Allah be pleased with him); I have already mentioned from al-Waqidi that he died in the year 21 AH.

Mus'ab bin Abdullah narrates that Sayyiduna Khalid bin al-Walid (may Allah be pleased with him) died in Madinah in the year 22 AH.

Khalifah bin Khayyat narrates that Sayyiduna Khalid bin al-Walid (may Allah be pleased with him) died in Syria, according to one view in Hims, in the year 21 AH; while Yahya bin Bukayr says that he died in Madinah in the year 17 or 18 AH.