Musnad Abu Ya'la al-Mawsili 160:236

Bishr ibn al-Walid narrated to us, Ishaq ibn Sa'id narrated to us, from Sa'id, from Abu Hurayrah, who said: "How will you be when you do not gather a dinar nor a dirham?" They said, "Do you see that happening?" He said, "Yes, by the One in Whose hand is the soul of Abu Hurayrah, based on the word of the Truthful, the Believed." They said, "And because of what will this be?" He said, "The covenant of Allah and the covenant of His Messenger will be violated, so Allah will harden the hearts of the people of the covenant (dhimmis), and they will withhold what is in their hands."