Sunan an-Nasa'i 3768
سنن النسائي#3768Sahihأَخْبَرَنَا عَمْرُو بْنُ عُثْمَانَ بْنِ سَعِيدٍ، قَالَ أَنْبَأَنَا مُحَمَّدٌ، - وَهُوَ ابْنُ حَرْبٍ - عَنِ الزُّبَيْدِيِّ، عَنِ الزُّهْرِيِّ، عَنْ سَالِمٍ، عَنْ أَبِيهِ، أَنَّهُ أَخْبَرَهُ عَنْ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " إِنَّ اللَّهَ يَنْهَاكُمْ أَنْ تَحْلِفُوا بِآبَائِكُمْ " . قَالَ عُمَرُ فَوَاللَّهِ مَا حَلَفْتُ بِهَا بَعْدُ ذَاكِرًا وَلاَ آثِرًا .
It was narrated from Salim, from his father, that he told him from 'Umar:"The Messenger of Allah said: 'Allah forbids you to swear by your forefathers.'" 'Umar said: "By Allah, I never swore by them again, whether saying it for myself or reporting it of others
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: 35:8