This hadeeth comes under the following chapter: THE MERIT OF HELPING THE WARRIOR (FIGHTING IN THE WAY OF ALLAAH) WITH SOMETHING TO RIDE UPOW 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 Allaah (sallAllaahu alayhi wa sallam) 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.