ʿUbaydullāh b. Saʿīd > Yaḥyá > ʿUbaydullāh > Nāfiʿ > ʿAbdullāh

That the Messenger of Allah ﷺ came across 'Umar while he was on his mount, and he was swearing by his father. So the Messenger of Allah ﷺ said: "Verily Allah prohibits you from swearing by your fathers. So let the one who swears, swear by Allah, or be silent."

أَخْبَرَنَا عُبَيْدُ اللهِ بْنُ سَعِيدٍ قَالَ حَدَّثَنَا يَحْيَى عَنْ عُبَيْدِ اللهِ عَنْ نَافِعٍ عَنْ عَبْدِ اللهِ

أَنَّ رَسُولَ اللهِ ﷺ أَدْرَكَ عُمَرَ فِي رَكْبٍ يَحْلِفُ بِأَبِيهِ فَقَالَ «إِنَّ اللهَ يَنْهَاكُمْ أَنْ تَحْلِفُوا بِآبَائِكُمْ حَالِفٌ يَحْلِفُ بِاللهِ أَوْ لِيَسْكُتْ»