During the time of the Messenger of Allah ﷺ, we used to be called brokers. The Messenger of Allah ﷺ passed by us and gave us a better name, saying, "Company of merchants, selling involves swearing of oaths and idle talk, so mix it with charity."
حدثنا محمد بن عبد الله بن نمير حدثنا أبو معاوية عن الأعمش عن شقيق
كنا نسمى في عهد رسول الله ﷺ السماسرة فمر بنا رسول الله ﷺ فسمانا باسم هو أحسن منه فقال يا معشر التجار إن البيع يحضره الحلف واللغو فشوبوه بالصدقة
[Sahih] Abu Dawud narrated it in the Book of Business Transactions, chapter: On trade mixed with oath-taking and idle talk, hadith: 3326, from the hadith of Abu Muawiya with this wording. Tirmidhi graded it sahih, hadith: 1208, as did Ibn Jarud, hadith: 557, Hakim, 5/2, and Dhahabi.Amash stated clearly that he heard [the hadith directly] - Mushkil Athar by Tahawi, 3/13-14 - and a group of narrators corroborated him.