Sahih Muslim
Sahih Muslim 110a
حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، أَخْبَرَنَا مُعَاوِيَةُ بْنُ سَلاَّمِ بْنِ أَبِي سَلاَّمٍ الدِّمَشْقِيُّ، عَنْ يَحْيَى بْنِ أَبِي كَثِيرٍ، أَنَّ أَبَا قِلاَبَةَ، أَخْبَرَهُ أَنَّ ثَابِتَ بْنَ الضَّحَّاكِ أَخْبَرَهُ أَنَّهُ، بَايَعَ رَسُولَ اللَّهِ صلى الله عليه وسلم تَحْتَ الشَّجَرَةِ وَأَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " مَنْ حَلَفَ عَلَى يَمِينٍ بِمِلَّةٍ غَيْرِ الإِسْلاَمِ كَاذِبًا فَهُوَ كَمَا قَالَ وَمَنْ قَتَلَ نَفْسَهُ بِشَىْءٍ عُذِّبَ بِهِ يَوْمَ الْقِيَامَةِ وَلَيْسَ عَلَى رَجُلٍ نَذْرٌ فِي شَىْءٍ لاَ يَمْلِكُهُ " .
Yahya ibn Yahya narrated to us; Mu'awiyah ibn Sallam ibn Abi Sallam al-Dimashqi informed us, from Yahya ibn Abi Kathir, that Abu Qilabah informed him that Thabit ibn al-Dahhak informed him that he pledged allegiance to the Messenger of Allah (peace and blessings be upon him) beneath the tree. The Messenger of Allah said: ‘Whoever falsely swears by a religion other than Islam is as he declared himself to be. Whoever kills himself with something will be punished with it on the Day of Resurrection. A man is not bound by a vow concerning something he does not own.’