(1) باب فِي التِّجَارَةِ يُخَالِطُهَا الْحَلِفُ وَاللَّغْوُ
Narrated Qays ibn AbuGharazah:
In the time of the Messenger of Allah (ﷺ) we used to be called brokers, but the Prophet (ﷺ) came upon us one day, and called us by a better name than that, saying: O company of merchants, unprofitable speech and swearing takes place in business dealings, so mix it with sadaqah (alms).
Reference: Sunan Abi Dawud 3326
In-book reference: Book 23, Hadith 1
English translation: Book 22, Hadith 3320