مِشْكَاةُ الْمَصَابِيحِ
Mishkat al-Masabih 3795
Jihad
(Section III) - Section 1
وَعَنْ أَبِي هُرَيْرَةَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «لَا يَجْتَمِعُ كَافِرٌ وَقَاتِلُهُ فِي النَّارِ أبدا» . رَوَاهُ مُسلم
Abu Huraira reported God's Messenger as saying, “An infidel and the one who killed him will never be brought together in hell.”* * The meaning is probably that one who kills an infidel in the course of jihad will on that account have his sins forgiven, and will therefore not go to hell where the infidel inevitably goes. Muslim transmitted it.
Mishkat al-Masabih, 3795صَحِيح (الألباني)