Al-Kāfi

Hadith 480
fastingramadan
2ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ حَمَّادٍ عَنِ الْحَلَبِيِّ قَالَ سَأَلْتُ أَبَا عَبْدِ الله (عَلَيْهِ السَّلاَم) عَنِ الرَّجُلِ عَلَيْهِ مِنْ شَهْرِ رَمَضَانَ طَائِفَةٌ أَ يَتَطَوَّعُ فَقَالَ لا حَتَّى يَقْضِيَ مَا عَلَيْهِ مِنْ شَهْرِ رَمَضَانَ.
2. Ali ibn Ibrahim has narrated from his father from ibn abu ‘ Umayr from Hammad from al-Halabiy who has said the following: “I asked abu ‘Abdillah (a.s.) about a man who owes Qada’ (compensatory fast) of the month of Ramadan if he can fast an optional fast.‘ He (the Imam) replied, ‘No, he cannot do so before completing the Qada’ (compensatory fast) of the month of Ramadan.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī