Sahih al-Bukhari 3956
Sahih al-Bukhari · Book 64: Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi) · The number of the warriors of Badr
Narrated Al-Bara:
حَدَّثَنِي مَحْمُودٌ ، حَدَّثَنَا وَهْبٌ ، عَنْ شُعْبَةَ ، عَنْ أَبِي إِسْحَاقَ ، عَنِ الْبَرَاءِ ، قَالَ اسْتُصْغِرْتُ أَنَا وَابْنُ عُمَرَ يَوْمَ بَدْرٍ، وَكَانَ الْمُهَاجِرُونَ يَوْمَ بَدْرٍ نَيِّفًا عَلَى سِتِّينَ، وَالأَنْصَارُ نَيِّفًا وَأَرْبَعِينَ وَمِائَتَيْنِ.
I and Ibn `Umar were considered too young (to take part) in the battle of Badr, and the number of the Emigrant warriors were over sixty (men) and the Ansar were over 249.