Ṣaḥīḥ al-Bukhārī
صَحِيحُ البُخَارِي
Considered to be the most authentic after the Qurʾān. Full name: al-Jāmiʿ al-Musnad al-Ṣaḥīḥ al-Mukhtaṣar min Umūr Rasūlallāh ﷺ wa-Sunnatihī wa-Ayyāmihī (الجامع المسند الصحيح المختصر من أمور رسول الله ﷺ وأيامه) (The Comprehensive Summarized Authentic Chains from the Affairs of the Messenger of Allah ﷺ, his Sunnah, and his Life and Times). Sources: sunnah.com for the Arabic text and English translation. The English translation has been improved by myself and other contributors.
Random ḥadīth in Bukhārī
I gave a horse in Allah's Cause. The person to whom it was given, did not look after it. I intended to buy it from him, thinking that he would sell it cheap. When I asked the Prophet ﷺ he said, "Don't buy it, even if he gives it to you for one Dirham, as the person who takes back what he has given in charity, is like a dog that swallows back its vomit."
عَنْ ذَلِكَ النَّبِيَّ ﷺ فَقَالَ لاَ تَشْتَرِهِ وَإِنْ أَعْطَاكَهُ بِدِرْهَمٍ وَاحِدٍ فَإِنَّ الْعَائِدَ فِي صَدَقَتِهِ كَالْكَلْبِ يَعُودُ فِي قَيْئِهِ