Sunan an-Nasa'i 3789
سنن النسائي#3789Sahihأَخْبَرَنَا زِيَادُ بْنُ أَيُّوبَ، قَالَ حَدَّثَنَا هُشَيْمٌ، قَالَ أَنْبَأَنَا مَنْصُورٌ، وَيُونُسُ، عَنِ الْحَسَنِ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ سَمُرَةَ، قَالَ قَالَ لِي النَّبِيُّ صلى الله عليه وسلم " إِذَا آلَيْتَ عَلَى يَمِينٍ فَرَأَيْتَ غَيْرَهَا خَيْرًا مِنْهَا فَأْتِ الَّذِي هُوَ خَيْرٌ وَكَفِّرْ عَنْ يَمِينِكَ " .
It was narrated that 'Abdur-Rahman bin Samurah said:"The Prophet said to me: 'If you swear an oath, and you see something that is better, then 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: 35:29