Musannaf Ibn Abi Shayba 21:431

Narrated to us Abdullah ibn Numayr, from al-A’mash, from Abu Salih, from Abu Hurayrah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "O Allah, I am only a human being, so whichever man among the Muslims I have insulted, cursed, or whipped, make it a purification and a mercy for him."