In the prohibition of envy

Khālid b. Makhlad > Mālik > Nāfiʿ > Ibn ʿUmar

"The Messenger of Allah ﷺ prohibited 'shighar'. Malik said, 'Shighar' is when a man gives his daughter in marriage to another man, while that man gives his daughter in marriage to the first man, without any dowry. Abu Muhammad was asked, 'Do you consider marriage between them valid?' He said, 'I do not approve of it.'" – Strong Chain

حَدَّثَنَا خَالِدُ بْنُ مَخْلَدٍ حَدَّثَنَا مَالِكٌ عَنْ نَافِعٍ عَنْ ابْنِ عُمَرَ قَالَ

«نَهَى رَسُولُ اللَّهِ ﷺ عَنِ الشِّغَارِ» قَالَ مَالِكٌ وَالشِّغَارُ أَنْ يُزَوِّجَ الرَّجُلُ الْآخَرَ ابْنَتَهُ عَلَى أَنْ يُزَوِّجَهُ الْآخَرُ ابْنَتَهُ بِغَيْرِ صَدَاقٍ قِيلَ لِأَبِي مُحَمَّدٍ تَرَى بَيْنَهُمَا نِكَاحًا قَالَ لَا يُعْجِبُنِي – إسناده قوي