Sunan an-Nasa'i, Hadith 5029 ⓘ
Abu Hurairah said: "I heard the Messenger of Allah [SAW] say: 'Allah has promised the one who goes out in His cause 'and does not go out except with faith in Me and for Jihad in My cause,' that he is guaranteed to enter Paradise no matter how, either he is killed, or he dies, or he will be brought back to his home from which he departed having acquired whatever he acquired of reward or spoils of war.'"
أَخْبَرَنَا قُتَيْبَةُ قَالَ حَدَّثَنَا اللَّيْثُ عَنْ سَعِيدٍ عَنْ عَطَاءِ بْنِ مِينَاءَ سَمِعَ أَبَا هُرَيْرَةَ يَقُولُ سَمِعْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ انْتَدَبَ اللَّهُ لِمَنْ يَخْرُجُ فِي سَبِيلِهِ لَا يُخْرِجُهُ إِلَّا الْإِيمَانُ بِي وَالْجِهَادُ فِي سَبِيلِي أَنَّهُ ضَامِنٌ حَتَّى أُدْخِلَهُ الْجَنَّةَ بِأَيِّهِمَا كَانَ إِمَّا بِقَتْلٍ وَإِمَّا وَفَاةٍ أَوْ أَنْ يَرُدَّهُ إِلَى مَسْكَنِهِ الَّذِي خَرَجَ مِنْهُ يَنَالُ مَا نَالَ مِنْ أَجْرٍ أَوْ غَنِيمَةٍ
also referenced under: Book 47, Hadith 45 (In-Book) & Volume 6, Book 47, Hadith 5032 (DarusSalam)