ENOfficial
Jabir reported God's Messenger as saying, “God show mercy to a man who is kindly when he sells, when he buys, and when he makes a claim!” Bukhari transmitted it.
Source: sunnah.com
Other translations
Arabic
عَنْ جَابِرٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: رَحِمَ اللَّهُ رَجُلًا سَمْحًا إِذَا بَاعَ وَإِذَا اشْتَرَى وَإِذَا اقْتَضَى رَوَاهُ البُخَارِيّ
sunnah.com