Full Sharh — Sahih al-Bukhari 3069
حَدَّثَنَا أَحْمَدُ بْنُ يُونُسَ، حَدَّثَنَا زُهَيْرٌ، عَنْ مُوسَى بْنِ عُقْبَةَ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما أَنَّهُ كَانَ عَلَى فَرَسٍ يَوْمَ لَقِيَ الْمُسْلِمُونَ، وَأَمِيرُ الْمُسْلِمِينَ يَوْمَئِذٍ خَالِدُ بْنُ الْوَلِيدِ، بَعَثَهُ أَبُو بَكْرٍ، فَأَخَذَهُ الْعَدُوُّ، فَلَمَّا هُزِمَ الْعَدُوُّ رَدَّ خَالِدٌ فَرَسَهُ.
English Translation
Narrated Ibn `Umar:That he was riding a horse on the day, the Muslims fought (against the Byzantines), and the commander of the Muslim army was Khalid bin Al-Walid who had been appointed by Abu Bakr. The enemy took the horse away, and when the enemy was defeated, Khalid returned the horse to him
Source
Sahih al-Bukhari(صحيح البخاري)
Fighting for the Cause of Allah (Jihaad)
Hadith Number
3069