Musnad Ahmad 30:602

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from Suhayl ibn Abi Salih, from his father, from Abu Hurayrah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "There is no man who does not pay the Zakat of his wealth except that it will be made into plates of fire on the Day of Resurrection, with which his side, his forehead, and his back will be branded, on a day the measure of which is fifty thousand years, until judgment is passed between the people, then he will see his path. And if it was camels, they will be laid out for him on a level, barren plain on a day the measure of which is fifty thousand years; they will trample him with their hooves—I think he said: and bite him with their mouths—the first of them returning to the last of them, until judgment is passed between the people, then he will see his path. And if it was sheep, it will be like that, except that they will gore him with their horns and trample him with their hooves."