Musannaf Ibn Abi Shayba 13:2229

Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Musa ibn ‘Ali narrated to us, from his father, he said: I heard ‘Amr ibn al-‘As saying: The Messenger of Allah (peace and blessings of Allah be upon him) said: "O ‘Amr, fasten your weapons and your clothes upon you, then come to me." He said: So I fastened my weapons and my clothes upon me, then I came to him and found him performing ablution. He looked at me, up and down, and said: "O ‘Amr, I want to send you on an expedition; Allah will keep you safe and grant you spoils, and I desire for you a good portion of wealth." He said: I said: "O Messenger of Allah, I did not accept Islam out of a desire for wealth; rather, I accepted Islam out of a desire for Jihad and to be with you." He said: "O ‘Amr, excellent is the good wealth for the righteous man."