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كتاب المغازى
64  
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
(9)
Chapter: Superiority of those who fought the battle of Badr
(9)
باب فَضْلُ مَنْ شَهِدَ بَدْرًا
Sahih al-Bukhari 3982

Narrated Anas:

Haritha was martyred on the day (of the battle) of Badr, and he was a young boy then. His mother came to the Prophet (ﷺ) and said, "O Allah's Messenger (ﷺ)! You know how dear Haritha is to me. If he is in Paradise, I shall remain patient, and hope for reward from Allah, but if it is not so, then you shall see what I do?" He said, "May Allah be merciful to you! Have you lost your senses? Do you think there is only one Paradise? There are many Paradises and your son is in the (most superior) Paradise of Al- Firdaus."

حَدَّثَنِي عَبْدُ اللَّهِ بْنُ مُحَمَّدٍ، حَدَّثَنَا مُعَاوِيَةُ بْنُ عَمْرٍو، حَدَّثَنَا أَبُو إِسْحَاقَ، عَنْ حُمَيْدٍ، قَالَ سَمِعْتُ أَنَسًا ـ رضى الله عنه ـ يَقُولُ أُصِيبَ حَارِثَةُ يَوْمَ بَدْرٍ وَهْوَ غُلاَمٌ، فَجَاءَتْ أُمُّهُ إِلَى النَّبِيِّ صلى الله عليه وسلم فَقَالَتْ يَا رَسُولَ اللَّهِ، قَدْ عَرَفْتَ مَنْزِلَةَ حَارِثَةَ مِنِّي، فَإِنْ يَكُنْ فِي الْجَنَّةِ أَصْبِرْ وَأَحْتَسِبْ، وَإِنْ تَكُ الأُخْرَى تَرَى مَا أَصْنَعُ فَقَالَ ‏ "‏ وَيْحَكِ أَوَهَبِلْتِ أَوَجَنَّةٌ وَاحِدَةٌ هِيَ إِنَّهَا جِنَانٌ كَثِيرَةٌ، وَإِنَّهُ فِي جَنَّةِ الْفِرْدَوْسِ ‏"‏‏.‏
Reference : Sahih al-Bukhari 3982
In-book reference : Book 64, Hadith 33
USC-MSA web (English) reference : Vol. 5, Book 59, Hadith 318
  (deprecated numbering scheme)