مشكوة المصابيح
Mishkat al-Masabih
كتاب الإيمان والنذور
The Book of Oaths and Vows
(بَيَانُ صِدْقِ مَنْ يَحْلِفُ)
(Explanation of the truthfulness of one who takes an oath)
Hadith 3415
وَعَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «يَمِينُكَ عَلَى مَا يُصَدِّقُكَ عَلَيْهِ صَاحبك» . رَوَاهُ مُسلم
He reported God’s Messenger as saying, "Your oath should be about something regarding which your companion will believe you.” Muslim transmitted it.
