Sahih Muslim , Book 33, Hadith 202 (In-Book) ⓘ
It has been narrated (through a still different chain of transmitters) on the authority of Abu Sa'id Khudrl that the Messenger of Allah despatched a force to Banu Lihyan. (and said: ) 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.
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 " .
also referenced under: Hadith 1896 (Reference) & Book 20, Hadith 4672 (USC-MSA)