رِيَاضُ الصَّالِحِينَ
Riyad as-Salihin 1721
The Book of the Prohibited actions
Abomination of Swearing in Transaction
عَنْ أَبِي قَتَادَةَ رَضِيَ اللَّه عَنْهُ أَنَّهُ سَمِعَ رَسُولَ اللَّهِ صَلَّى اللَّه عَلَيْهِ وَسَلَّمَ يَقُولُ: إِيَّاكُمْ وَكَثْرَةَ الْحَلِفِ فِي الْبَيْعِ، فَإِنَّهُ يُنَفِّقُ ثُمَّ يَمْحَقُ ((رَوَاهُ مُسلم)).
Abu Qatadah (May Allah be pleased with him) said: I heard the Messenger of Allah (ﷺ) saying, "Beware of excessive swearing in sale, because it may promote trade but this practice will eliminate the blessing." [Muslim].
Riyad as-Salihin, 1721