وَحَدَّثَنِي أَبُو الطَّاهِرِ، أَخْبَرَنَا عَبْدُ اللَّهِ بْنُ وَهْبٍ، عَنِ اللَّيْثِ، وَغَيْرِهِ، عَنْ يَزِيدَ بْنِ، أَبِي حَبِيبٍ عَنْ عَبْدِ الرَّحْمَنِ بْنِ شُمَاسَةَ، أَنَّهُ سَمِعَ عُقْبَةَ بْنَ عَامِرٍ، عَلَى الْمِنْبَرِ يَقُولُ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ
" الْمُؤْمِنُ أَخُو الْمُؤْمِنِ فَلاَ يَحِلُّ لِلْمُؤْمِنِ أَنْ يَبْتَاعَ عَلَى بَيْعِ أَخِيهِ وَلاَ يَخْطُبَ عَلَى خِطْبَةِ أَخِيهِ حَتَّى يَذَرَ " .
A believer is the brother of a believer, so it is not lawful for a believer to outbid his brother, and he should not propose an engagement when his brother has thus proposed until he gives it up.
Source: Sahih Muslim — repository translation · Imam Muslim ibn al-Hajjaj al-Naysaburi — authenticity/grade metadata requires independent source review · Sunnah.comAudio not available for the selected reciter.
Source: Sahih Muslim — repository arabic · Imam Muslim ibn al-Hajjaj al-Naysaburi · Sunnah.com