مشكوة المصابيح Mishkat al-Masabih كتاب الصوم The Book of Fasting
(شَرْطَانِ لِقَبُولِ الصِّيَامِ: ١. الإِيمَانُ ٢. الْاحْتِسَابُ)

(Two conditions for acceptance of fasting: 1. Faith 2. Accountability)

1 hadith
Hadith 1958
وَعَنْ أَبِي هُرَيْرَةَ رَضِيَ اللَّهُ عَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَنْ صَامَ رَمَضَانَ إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ. وَمَنْ قَامَ رَمَضَانَ إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ. وَمَنْ قَامَ لَيْلَةَ الْقَدْرِ إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ»
Abu Huraira reported God's messenger as saying, "He who fasts during Ramadan with faith and seeking his reward from God will have his past sins forgiven; he who prays during the night in Ramadan with faith and seeking his reward from God will have his past sins forgiven; and he who passes Lailat al-qadr [Night of Decree] in prayer with faith and seeking his reward from God will have his past sins forgiven." (Bukhari and Muslim.)
Hadith Reference Mishkat al-Masabih / The Book of Fasting / Hadith: 1958
Hadith Grading الألبانی: مُتَّفَقٌ عَلَيْهِ  |  زبیر علی زئی: متفق عليه
Hadith Takhrij ´تحقيق و تخريج: محدث العصر حافظ زبير على زئي رحمه الله` «متفق عليه، رواه البخاري (37) و مسلم (760/175)»