Musnad Ahmad 30:2444

Yahya ibn Sa'id al-Qattan narrated to us, from Sufyan, who said: Salamah ibn Kuhayl narrated to me, from Abu Salamah, from Abu Hurayrah, that a man demanded from the Messenger of Allah (peace and blessings of Allah be upon him) a camel [that was owed to him]. They said: "We do not find [one] except [one that is] better in age than his." He said: "Give it to him." The man said: "You have fulfilled [the debt] to me, may Allah fulfill [His reward] for you." He said: "The best of people are the best of them in repayment."