Sahih Muslim , Book 7, Hadith 2845 (USC-MSA)

Bakr b. 'Abdullah reported: Anas (Allah be pleased with him) had narrated to us that he saw Allah's Apostle combining Hajj and 'Umra. He (Bakr) said: I asked (about it) from Ibn 'Umar, whereupon he said: We entered into the state of Ihram for Hajj (only). I came to Anas and told him what Ibn Umar had said, whereupon he remarked: (You are treating us) as if we were children.

وَحَدَّثَنِي أُمَيَّةُ بْنُ بِسْطَامَ الْعَيْشِيُّ، حَدَّثَنَا يَزِيدُ، - يَعْنِي ابْنَ زُرَيْعٍ - حَدَّثَنَا حَبِيبُ، بْنُ الشَّهِيدِ عَنْ بَكْرِ بْنِ عَبْدِ اللَّهِ، حَدَّثَنَا أَنَسٌ، رضى الله عنه أَنَّهُ رَأَى النَّبِيَّ صلى الله عليه وسلم جَمَعَ بَيْنَهُمَا بَيْنَ الْحَجِّ وَالْعُمْرَةِ قَالَ فَسَأَلْتُ ابْنَ عُمَرَ فَقَالَ أَهْلَلْنَا بِالْحَجِّ ‏.‏ فَرَجَعْتُ إِلَى أَنَسٍ فَأَخْبَرْتُهُ مَا قَالَ ابْنُ عُمَرَ فَقَالَ كَأَنَّمَا كُنَّا صِبْيَانًا ‏.‏

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