Sahih al Bukhari 2811
Fighting for the Cause of Allah (Jihaad)
حَدَّثَنَا إِسْحَاقُ، أَخْبَرَنَا مُحَمَّدُ بْنُ الْمُبَارَكِ، حَدَّثَنَا يَحْيَى بْنُ حَمْزَةَ، قَالَ حَدَّثَنِي يَزِيدُ بْنُ أَبِي مَرْيَمَ، أَخْبَرَنَا عَبَايَةُ بْنُ رَافِعِ بْنِ خَدِيجٍ، قَالَ أَخْبَرَنِي أَبُو عَبْسٍ، هُوَ عَبْدُ الرَّحْمَنِ بْنُ جَبْرٍ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " مَا اغْبَرَّتْ قَدَمَا عَبْدٍ فِي سَبِيلِ اللَّهِ فَتَمَسَّهُ النَّارُ ".
Narrated Abu `Abs:(who is `Abdur-Rahman bin Jabir) Allah's Messenger (ﷺ) said," Anyone whose both feet get covered with dust in Allah's Cause will not be touched by the (Hell) fire
Text from the public-domain hadith-api dataset. Numbering follows that dataset and can differ by a few from some printed editions — check the wording, not only the number.