حَدَّثَنَا مَکِّيُّ بْنُ إِبْرَاهِيمَ حَدَّثَنَا ابْنُ جُرَيْجٍ قَالَ سَمِعْتُ نَافِعًا يُحَدِّثُ أَنَّ ابْنَ عُمَرَ رَضِيَ اللَّهُ عَنْهُمَا کَانَ يَقُولُ نَهَی النَّبِيُّ صَلَّی اللَّهُ عَلَيْهِ وَسَلَّمَ أَنْ يَبِيعَ بَعْضُکُمْ عَلَی بَيْعِ بَعْضٍ وَلَا يَخْطُبَ الرَّجُلُ عَلَی خِطْبَةِ أَخِيهِ حَتَّی يَتْرُکَ الْخَاطِبُ قَبْلَهُ أَوْ يَأْذَنَ لَهُ الْخَاطِبُ
صحیح بخاری · Hadith 5144
And none should ask for the hand of a girl who is already engaged to his (Muslim) brother, but one should wait till the first suitor marries her or leaves her."
Translated by Dr. Muhammad Muhsin Khan · Reviewed by Islamic University of Madinah · Published March 2020