Language:
كتاب الجهاد والسير
56  
Fighting for the Cause of Allah (Jihaad)
(19)
Chapter: The Statement of Allah Taa'la: "Think not of those who are killed in the Way of Allah as dead..."
(19)
بَابُ فَضْلِ قَوْلِ اللَّهِ تَعَالَى: {وَلاَ تَحْسِبَنَّ الَّذِينَ قُتِلُوا فِي سَبِيلِ اللَّهِ أَمْوَاتًا بَلْ أَحْيَاءٌ عِنْدَ رَبِّهِمْ يُرْزَقُونَ فَرِحِينَ بِمَا آتَاهُمُ اللَّهُ مِنْ فَضْلِهِ وَيَسْتَبْشِرُونَ بِالَّذِينَ لَمْ يَلْحَقُوا بِهِمْ مِنْ خَلْفِهِمْ أَنْ لاَ خَوْفٌ عَلَيْهِمْ وَلاَ هُمْ يَحْزَنُونَ يَسْتَبْشِرُونَ بِنِعْمَةٍ مِنَ اللَّهِ وَفَضْلٍ وَأَنَّ اللَّهَ لاَ يُضِيعُ أَجْرَ الْمُؤْمِنِينَ}
Sahih al-Bukhari 2814

Narrated Anas bin Malik:

For thirty days Allah's Messenger (ﷺ) invoked Allah to curse those who had killed the companions of Bir- Mauna; he invoked evil upon the tribes of Ral, Dhakwan, and Usaiya who disobeyed Allah and His Apostle. There was reveled about those who were killed at Bir-Mauna a Qur'anic Verse we used to recite, but it was cancelled later on. The Verse was: "Inform our people that we have met our Lord. He is pleased with us and He has made us pleased."

حَدَّثَنَا إِسْمَاعِيلُ بْنُ عَبْدِ اللَّهِ، قَالَ حَدَّثَنِي مَالِكٌ، عَنْ إِسْحَاقَ بْنِ عَبْدِ اللَّهِ بْنِ أَبِي طَلْحَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ ـ رضى الله عنه ـ قَالَ دَعَا رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى الَّذِينَ قَتَلُوا أَصْحَابَ بِئْرِ مَعُونَةَ ثَلاَثِينَ غَدَاةً، عَلَى رِعْلٍ وَذَكْوَانَ وَعُصَيَّةَ عَصَتِ اللَّهَ وَرَسُولَهُ، قَالَ أَنَسٌ أُنْزِلَ فِي الَّذِينَ قُتِلُوا بِبِئْرِ مَعُونَةَ قُرْآنٌ قَرَأْنَاهُ ثُمَّ نُسِخَ بَعْدُ بَلِّغُوا قَوْمَنَا أَنْ قَدْ لَقِينَا رَبَّنَا فَرَضِيَ عَنَّا وَرَضِينَا عَنْهُ‏.‏
Reference : Sahih al-Bukhari 2814
In-book reference : Book 56, Hadith 30
USC-MSA web (English) reference : Vol. 4, Book 52, Hadith 69
  (deprecated numbering scheme)