Musnad Ahmad 31:913

'Affan narrated to us, Hammad bin Salamah narrated to us, from 'Ali bin Zayd, from Abu Nadrah, from Abu Sa'id al-Khudri, that the Messenger of Allah (may Allah bless him and grant him peace) said: "Allah, the Almighty and Majestic, will surely send forth in this nation a Caliph who will scoop up wealth in handfuls and will not count it out."