It was narrated from Ibn 'Umar that the Prophet (ﷺ) said:

"No one of you should urge someone to cancel a sale he has already agreed upon with his brother so as to sell him his own goods."

أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، عَنْ مَالِكٍ، وَاللَّيْثِ، - وَاللَّفْظُ لَهُ - عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، عَنِ النَّبِيِّ صلى الله عليه وسلم أَنَّهُ قَالَ ‏

‏ لاَ يَبِيعُ أَحَدُكُمْ عَلَى بَيْعِ أَخِيهِ ‏

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