Al-Kāfi
Hadith 7954- مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنِ ابْنِ فَضَّالٍ عَنْ بَعْضِ أَصْحَابِنَا عَنْ أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلام) قَالَ مَنْ حَلَفَ عَلَى يَمِينٍ فَرَأَى مَا هُوَ خَيْرٌ مِنْهَا فَلْيَأْتِ الَّذِي هُوَ خَيْرٌ وَلَهُ حَسَنَةٌ.
4. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from ibn Faddal from certain persons of our people who have narrated the following: “Abu ‘Abd Allah (a.s.), has said, ‘If one takes an oath to do something then finds another thing better which he does, he must do that which is better; he gains one good deed.’”