Sunan an-Nasa'i 3791
سنن النسائي#3791Sahihأَخْبَرَنَا مُحَمَّدُ بْنُ قُدَامَةَ، فِي حَدِيثِهِ عَنْ جَرِيرٍ، عَنْ مَنْصُورٍ، عَنِ الْحَسَنِ الْبَصْرِيِّ، قَالَ عَبْدُ الرَّحْمَنِ بْنُ سَمُرَةَ قَالَ لِي رَسُولُ اللَّهِ صلى الله عليه وسلم " إِذَا حَلَفْتَ عَلَى يَمِينٍ فَرَأَيْتَ غَيْرَهَا خَيْرًا مِنْهَا فَأْتِ الَّذِي هُوَ خَيْرٌ وَكَفِّرْ عَنْ يَمِينِكَ " .
Abdur-Rahman bin Samurah said:"The Messenger of Allah said to me: 'If you swear an oath, then you see something that is better, do that which is better, and offer expiation for your oath
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 35:31