Musnad Ahmad 28:101

Abu Abd al-Rahman narrated to us, Haywah and Ibn Lahi'ah narrated to us, they said: Abu Hani' al-Khawlani narrated to us, that he heard Abu Abd al-Rahman al-Hubuli saying: I heard Abdullah ibn Amr ibn al-'As saying: I heard the Prophet, peace and blessings of Allah be upon him, saying: "There is no raiding party that raids in the way of Allah and obtains spoils of war, but that they have hastened two-thirds of their reward from the Hereafter, and one-third remains for them. But if they do not obtain any spoils of war, their reward is completed for them."