The Limits of Ablution, Its Order and Reward
Man Lā Yaḥḍuruh al-Faqīh|Volume 1|Book 1|Chapter 11
وَقَالَ أَبُو اَلْحَسَنِ مُوسَى بْنُ جَعْفَرٍ عَلَيْهِ اَلسَّلاَمُ: «مَنْ تَوَضَّأَ لِلْمَغْرِبِ كَانَ وُضُوؤُهُ ذَلِكَ كَفَّارَةً لِمَا مَضَى مِنْ ذُنُوبِهِ فِي نَهَارِهِ مَا خَلاَ اَلْكَبَائِرَ وَ مَنْ تَوَضَّأَ لِصَلاَةِ اَلصُّبْحِ كَانَ وُضُوؤُهُ ذَلِكَ كَفَّارَةً لِمَا مَضَى مِنْ ذُنُوبِهِ فِي لَيْلَتِهِ إِلاَّ اَلْكَبَائِرَ.
Abu Al-Hasan Imam Musa ibn Jafar Al-Kadhim عليه السلام said: 'Whoever performs ablution for the Maghrib prayer, his ablution serves as atonement for the sins he committed during the day, except for the major sins. And whoever performs ablution for the Fajr prayer, his ablution serves as atonement for the sins he committed during the night, except for the major sins.'"
- Ṣaḥīḥ al-Faqīh