Musannaf Ibn Abi Shaybah

Hazrat Malik bin Aws al-Hadthan (may Allah have mercy on him) narrates that Hazrat Umar (may Allah be pleased with him) said: The wealth of Banu Nadir which Allah granted to the Messenger of Allah (peace and blessings be upon him) was obtained by the Muslims without fighting; there was no need for combat in it. And this wealth was specific to the Noble Prophet (peace and blessings be upon him). He (peace and blessings be upon him) would set aside his yearly expenses from it, and whatever remained, he (peace and blessings be upon him) would allocate for horses and weapons, in preparation for using them in the path of Allah.