Ḥumayd b. Masʿadah > Bishr / Ibn al-Mufaḍḍal > Shuʿbah > Qatādah > Anas

"The Messenger of Allah [SAW] wanted to write to the Romans, but they (the Companions) said: 'They do not read any letter unless it has a seal.' So he took a ring of silver, and it is as if I can see its whiteness on his hand, and on it were engraved (the words): "Muhammad Rasul Allah (Muhammad the Messenger of Allah)."

أَخْبَرَنَا حُمَيْدُ بْنُ مَسْعَدَةَ عَنْ بِشْرٍ وَهُوَ ابْنُ الْمُفَضَّلِ قَالَ حَدَّثَنَا شُعْبَةُ عَنْ قَتَادَةَ عَنْ أَنَسٍ قَالَ

أَرَادَ رَسُولُ اللهِ ﷺ أَنْ يَكْتُبَ إِلَى الرُّومِ فَقَالُوا «إِنَّهُمْ لَا يَقْرَءُونَ كِتَابًا إِلَّا مَخْتُومًا فَاتَّخَذَ خَاتَمًا مِنْ فِضَّةٍ كَأَنِّي أَنْظُرُ إِلَى بَيَاضِهِ فِي يَدِهِ وَنَقَشَ فِيهِ مُحَمَّدٌ رَسُولُ اللهِ»