Narrated by:Ibn 'Abbas said
It was narrated that Ibn 'Abbas said:"The Messenger of Allah passed by a man who was leading another man by a rope. The Prophet took it, and cut it, and he said: 'It is a vow.'"
أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا خَالِدٌ، عَنِ ابْنِ جُرَيْجٍ، قَالَ حَدَّثَنِي سُلَيْمَانُ الأَحْوَلُ، عَنْ طَاوُسٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ مَرَّ رَسُولُ اللَّهِ صلى الله عليه وسلم بِرَجُلٍ يَقُودُ رَجُلاً فِي قَرَنٍ فَتَنَاوَلَهُ النَّبِيُّ صلى الله عليه وسلم فَقَطَعَهُ قَالَ إِنَّهُ نَذْرٌ .
Nesai
The Book of Oaths and Vows • Hadith 3810