The Book of Prayer
Bulugh al-Maram #435
كتاب الصلاة
وَعَنْ أُمِّ حَبِيبَةَ أُمِّ اَلْمُؤْمِنِينَ -رَضِيَ اَللَّهُ عَنْهَا- قَالَتْ: سَمِعْتَ اَلنَّبِيَّ - صلى الله عليه وسلم -يَقُولُ: «مَنْ صَلَّى اِثْنَتَا عَشْرَةَ رَكْعَةً فِي يَوْمٍ وَلَيْلَةٍ بُنِيَ لَهُ بِهِنَّ بَيْتٌ فِي اَلْجَنَّةِ» رَوَاهُ مُسْلِمٌ. وَفِي رِوَايَةٍ «تَطَوُّعًا».
Narrated Umm Habibah (RA) the Mother of the Believers:
She heard Allah's Messenger (ﷺ) say, “Whoever prays twelve (voluntary) Rak'at in a day and a night, a house will be built for him in Paradise due to them (the Rak'at).”
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In another narration, it is mentioned: “Voluntarily”.
وَعَنْ أُمِّ حَبِيبَةَ أُمِّ اَلْمُؤْمِنِينَ -رَضِيَ اَللَّهُ عَنْهَا- قَالَتْ : سَمِعْتَ اَلنَّبِيَّ - صلى الله عليه وسلم -يَقُولُ : "مَنْ صَلَّى اِثْنَتَا عَشْرَةَ رَكْعَةً فِي يَوْمٍ وَلَيْلَةٍ بُنِيَ لَهُ بِهِنَّ بَيْتٌ فِي اَلْجَنَّةِ" رَوَاهُ مُسْلِمٌ . وَفِي رِوَايَةٍ " تَطَوُّعًا" .
She heard Allah's Messenger (ﷺ) say, "Whoever prays twelve (voluntary) Rak'at in a day and a night, a house will be built for him in Paradise due to them (the Rak'at)." . In another narration, it is mentioned: "Voluntarily".
— Bulugh al-Maram, Hadith 435