Mishkat al-Masabih 30 Fine Qualities كتاب المناقب 277

وَعَنْ قَتَادَةَ قَالَ مَا نَعْلَمُ حَيًّا مِنْ أَحْيَاءِ الْعَرَبِ أَكْثَرَ شَهِيدًا أَعَزَّ يَوْمَ الْقِيَامَةِ مِنَ الْأَنْصَارِ. قَالَ: وَقَالَ أَنَسٌ: قُتِلَ مِنْهُمْ يَوْمَ أُحُدٍ سَبْعُونَ وَيَوْمَ بِئْرِ مَعُونَةَ سَبْعُونَ وَيَوْمَ الْيَمَامَةِ عَلَى عَهْدِ أَبِي بَكْرٍ سَبْعُونَ. رَوَاهُ البُخَارِيّ

Qatada said: We know no clan of the Arabs which will have more martyrs or be more exalted on the day of resurrection than the Ansar. He told that Anas said seventy of them were killed at the battle of Uhud, seventy at the battle of Bi’r Ma’una[1], and seventy at the battle of al-Yamama[2] in the time of Abu Bakr. 1. In Safar, 4 A.H. 2. 11 A.H., when Musailima was killed. Bukhari transmitted it.