Musnad Ahmad 937:269

Abdullah narrated to us, Ahmad ibn Muhammad ibn Ayyub Abu Ja’far narrated to us, Abu Bakr—meaning Ibn Ayyash—narrated to us, from Mutarrif, from Abu al-Jahm, from Khalid ibn Wahban, from Abu Dharr, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "O Abu Dharr, how will you be when you are under rulers who will withhold this booty from you?" He said: "By the One who sent you with the truth, I will place my sword upon my shoulder and strike with it until I join you." He said: "Shall I not guide you to that which is better for you than that? You should be patient until you meet me."