Chapter on Oaths, Vows, and Expiations
Man Lā Yaḥḍuruh al-Faqīh|Volume 3|Book 2|Chapter 38
وَ سَأَلَ إِسْمَاعِيلُ بْنُ سَعْدٍ أَبَا اَلْحَسَنِ اَلرِّضَا عَلَيْهِ اَلسَّلاَمُ: عَنِ اَلرَّجُلِ يَحْلِفُ بِالْيَمِينِ وَ ضَمِيرُهُ عَلَى غَيْرِ مَا حَلَفَ قَالَ "اَلْيَمِينُ عَلَى اَلضَّمِيرِ".
Isma'il ibn Sa'd asked Abu al-Hasan Imam Ali ibn Musa Ar-Ridha عليه السلام about a man who swears an oath, but his intention in the oath differs from the apparent wording. Imam عليه السلام said: "The oath is based on the intention."
- Ṣaḥīḥ al-Faqīh, p. 266