Fighting for the Cause of Allah (Jihaad)
حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا بِشْرُ بْنُ الْمُفَضَّلِ، حَدَّثَنَا خَالِدُ بْنُ ذَكْوَانَ، عَنِ الرُّبَيِّعِ بِنْتِ مُعَوِّذٍ، قَالَتْ كُنَّا مَعَ النَّبِيِّ صلى الله عليه وسلم نَسْقِي، وَنُدَاوِي الْجَرْحَى، وَنَرُدُّ الْقَتْلَى إِلَى الْمَدِينَةِ.Narrated Ar-Rubayyi 'bint Mu'auwidh:We were in the company of the Prophet (ﷺ) providing the wounded with water and treating them and bringing the killed to Medina (from the battle field)
From Sahih al-Bukhari, whose reports the scholars accept as authentic.