Sahih al-Bukhari, Hadith 1521

Narrated Abu Huraira: The Prophet (p.b.u.h) said, "Whoever performs Hajj for Allah's pleasure and does not have sexual relations with his wife, and does not do evil or sins then he will return (after Hajj free from all sins) as if he were born anew."

حَدَّثَنَا آدَمُ، حَدَّثَنَا شُعْبَةُ، حَدَّثَنَا سَيَّارٌ أَبُو الْحَكَمِ، قَالَ سَمِعْتُ أَبَا حَازِمٍ، قَالَ سَمِعْتُ أَبَا هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ سَمِعْتُ النَّبِيَّ صلى الله عليه وسلم يَقُولُ ‏ "‏ مَنْ حَجَّ لِلَّهِ فَلَمْ يَرْفُثْ وَلَمْ يَفْسُقْ رَجَعَ كَيَوْمِ وَلَدَتْهُ أُمُّهُ ‏" ‏‏.‏

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