Sunan At-Tirmidhi

Narrated Anas bin Malik: ""The Messenger of Allah (ﷺ) had a ring made from silver, so he had 'Muhammad, the Messenger of Allah' engraved on it. Then he said: 'Do not engrave with it.' [Abu 'Eisa said:] This Hadith is Sahih Hasan. As for the meaning of his saying: ""Do not engrave with it"" - he was prohibiting that anyone have ""Muhammad, Messenger of Allah"" engraved on his ring