Sahih Muslim Book - 33, Hadith - 4861

وَحَدَّثَنَا يَحْيَى بْنُ يَحْيَى أَخْبَرَنَا الْمُغِيرَةُ بْنُ عَبْدِ الرَّحْمَنِ الْحِزَامِىُّ عَنْ أَبِى الزِّنَادِ عَنِ الأَعْرَجِ عَنْ أَبِى هُرَيْرَةَ عَنِ النَّبِىِّ -صلى الله عليه وسلم- قَالَ « تَكَفَّلَ اللَّهُ لِمَنْ جَاهَدَ فِى سَبِيلِهِ لاَ يُخْرِجُهُ مِنْ بَيْتِهِ إِلاَّ جِهَادٌ فِى سَبِيلِهِ وَتَصْدِيقُ كَلِمَتِهِ - بِأَنْ يُدْخِلَهُ الْجَنَّةَ أَوْ يَرْجِعَهُ إِلَى مَسْكَنِهِ الَّذِى خَرَجَ مِنْهُ مَعَ مَا نَالَ مِنْ أَجْرٍ أَوْ غَنِيمَةٍ ».

It was narrated from Abu Hurairah that the Prophet (s.a.w) said: "Allah has given a guarantee to the one who fights in His cause and does not go out of his house except to fight in Jihad for His cause and to affirm His words, but He will either admit him to Paradise or bring him back to his home from which he departed, with whatever he has attained of reward or spoils of war."