Musnad Ahmad 30:754

Ishaq ibn Sulayman narrated to us, he said: I heard Hanzalah ibn Abi Sufyan, I heard Salim ibn Abdullah saying: I do not know how many times I saw Abu Hurayrah standing in the marketplace saying: "Knowledge will be seized, tribulations will appear, and *al-harj* will increase." It was said: "O Messenger of Allah, and what is *al-harj*?" He said with his hand like this, and he turned it.