Sahih Muslim 1896
Sahih Muslim · Book 33: The Book on Government · The virtue of helping the warrior who is fighting in the cause of Allah with mounts etc., and looking after his family in his absence
It has been narrated (through a still different chain of transmitters) on the authority of Abu Sa'id Khudrl that the Messenger of Allah (ﷺ) despatched a force to Banu Lihyan. (and said:
وَحَدَّثَنَا سَعِيدُ بْنُ مَنْصُورٍ ، حَدَّثَنَا عَبْدُ اللَّهِ بْنُ وَهْبٍ ، أَخْبَرَنِي عَمْرُو بْنُ الْحَارِثِ ، عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ ، عَنْ يَزِيدَ بْنِ أَبِي سَعِيدٍ ، مَوْلَى الْمَهْرِيِّ عَنْ أَبِيهِ ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم بَعَثَ إِلَى بَنِي لَحْيَانَ " لِيَخْرُجْ مِنْ كُلِّ رَجُلَيْنِ رَجُلٌ " . ثُمَّ قَالَ لِلْقَاعِدِ " أَيُّكُمْ خَلَفَ الْخَارِجَ فِي أَهْلِهِ وَمَالِهِ بِخَيْرٍ كَانَ لَهُ مِثْلُ نِصْفِ أَجْرِ الْخَارِجِ " .
) One man from every two should join the force. Then he said to those who stayed behind: Those of you who will look well after the family and wealth of those who are going on the expedition will be getting half the reward of the warriors.