When the Prophet ﷺ wanted to write to the Romans, he was told, "They will not read any letter unless it is sealed."So he had a silver ring made, and it is as if I can still see its whiteness on his hand. Engraved on it was, "Muhammad, Messenger of Allah."In another narration, he wanted to write to the non-Arabs.In a third narration, he wanted to write to Chosroes, Caesar, and the Negus.
لما أراد النبي ﷺ أن يكتب إلى الروم قيل له: إنهم لا يقرؤون كتابا إلا أن يكون مختوما، فاتخذ خاتما من فضة فكأني أنظر إلى بياضه في يده، ونقش فيه: محمد رسول الله. وفي رواية: أراد أن يكتب إلى العجم. وفي رواية ثالثة: أراد أن يكتب إلى كسرى وقيصر والنجاشي.
Bukhari narrated it in the Book of Jihad and Military Expeditions (2938), and Muslim narrated it in the Book of Clothing (2091:56), both of them through the route of Shuba, from Qatada, from Anas, and he related it. Muslim also narrated it (2091:57) through the route of Hisham, from Qatada, from him, with the second wording. And Muslim narrated it (2091:58) through the route of Khalid bin Qays, from Qatada, from him, with the third wording.And it was narrated from Miswar bin Makhrama, who said, the Messenger of Allah came out to his companions and said, "Allah, mighty and glorious, has sent me as a mercy to all people, so convey on my behalf, may Allah have mercy on you, and do not differ as the disciples differed regarding Isa, for he called them to the same thing I am calling you to. Those whose place was near responded and submitted, but those whose place was far disliked it, so Isa bin Maryam complained of that to Allah. The next morning each of them was speaking the language of the people to whom he had been sent, and Isa bin Maryam said to them, 'This is a matter Allah has decreed for you, so go forth and do it.'"The companions of the Messenger of Allah said, "We, O Messenger of Allah, will convey on your behalf, so send us wherever you wish." So the Messenger of Allah sent Abdullah bin Hudhafa to Khusraw, and sent Sulayt bin Amr to Hawdha bin Ali, the ruler of Yamama, and sent Ala bin Hadrami to Mundhir bin Sawa, the ruler of Hajr, and sent Amr bin As to Jayfar and Abbad, the two sons of Julanda, the two kings of Oman, and sent Dihya Kalbi to Caesar, and sent Shuja bin Wahb Asadi to Mundhir bin Harith bin Abu Shamir Ghassani, and sent Amr bin Umaya Damri to Najashi. They all returned before the death of the Messenger of Allah, except Ala bin Hadrami, for the Messenger of Allah died while he was in Bahrain.Tabarani narrated it in Al-Kabir (8/20–9) from Hashim bin Marthad Tabarani, who said, Muhammad bin Ismail bin Ayyash told us, from his father Ismail bin Ayyash, who said, Muhammad bin Ishaq told me, from Muhammad bin Muslim Zuhri, from Urwa bin Zubayr, from Miswar bin Makhrama, and he related it.In its chain is Muhammad bin Ismail bin Ayyash, whom they criticized for reporting from his father without having actually heard from him. His father, Ismail bin Ayyash, is truthful in his narrations from the people of Syria but confused in others, and his source here is from Madinah. And Muhammad bin Ishaq is a mudallis and he narrated using "an" (an ambiguous form suggesting he did not state direct hearing).Ibn Hisham said in Al-Sira (2/606–607), someone I trust told me, from Abu Bakr Hudhali, who said, it has reached me that the Messenger of Allah came out to his companions one day after the umrah from which he had been turned back on the day of Hudaybiya, and said, "O people, Allah has sent me as a mercy..." and he related something similar.