The Book of Marriage (Kitab Al-Nikah)

Muslim :: Book 8 : Hadith 3294

'Uqba b. 'Amir said on the pulpit that Allah's Messenger (may peace be upon him) said: 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 materials are from the University of Southern California MSA site
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