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كتاب التوحيد
97  
Oneness, Uniqueness of Allah (Tawheed)
(28)
Chapter: “And, verily, Our Word has gone forth of old for Our slaves – the Messengers”
(28)
Sahih al-Bukhari 7456

Narrated `Abdullah:

While I was walking with Allah's Messenger (ﷺ) in one of the fields of Medina and he was walking leaning on a stick, he passed a group of Jews. Some of them said to the others, "Ask him (the Prophet) about the spirit." Others said, "Do not ask him." But they asked him and he stood leaning on the stick and I was standing behind him and I thought that he was being divinely inspired. Then he said, "They ask you concerning the spirit say: The spirit, its knowledge is with My Lord. And of knowledge you (O men!) have been given only a little." ...(17.85) On that some of the Jews said to the others, "Didn't we tell you not to ask?"

حَدَّثَنَا يَحْيَى، حَدَّثَنَا وَكِيعٌ، عَنِ الأَعْمَشِ، عَنْ إِبْرَاهِيمَ، عَنْ عَلْقَمَةَ، عَنْ عَبْدِ اللَّهِ، قَالَ كُنْتُ أَمْشِي مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم فِي حَرْثٍ بِالْمَدِينَةِ وَهْوَ مُتَّكِئٌ عَلَى عَسِيبٍ، فَمَرَّ بِقَوْمٍ مِنَ الْيَهُودِ فَقَالَ بَعْضُهُمْ لِبَعْضٍ سَلُوهُ عَنِ الرُّوحِ‏.‏ وَقَالَ بَعْضُهُمْ لاَ تَسْأَلُوهُ عَنِ الرُّوحِ‏.‏ فَسَأَلُوهُ فَقَامَ مُتَوَكِّئًا عَلَى الْعَسِيبِ وَأَنَا خَلْفَهُ، فَظَنَنْتُ أَنَّهُ يُوحَى إِلَيْهِ فَقَالَ ‏{‏وَيَسْأَلُونَكَ عَنِ الرُّوحِ قُلِ الرُّوحُ مِنْ أَمْرِ رَبِّي وَمَا أُوتِيتُمْ مِنَ الْعِلْمِ إِلاَّ قَلِيلاً‏}‏ فَقَالَ بَعْضُهُمْ لِبَعْضٍ قَدْ قُلْنَا لَكُمْ لاَ تَسْأَلُوهُ‏.‏
Reference : Sahih al-Bukhari 7456
In-book reference : Book 97, Hadith 82
USC-MSA web (English) reference : Vol. 9, Book 93, Hadith 548
  (deprecated numbering scheme)