Musnad Ahmad 28:508

Abu Nu'aym narrated to us, al-A'mash narrated to us, from 'Amr ibn Murrah, who said: We were sitting with Abu 'Ubaydah, and they mentioned showing off (riya'). A man whose kunya was Abu Yazid said: I heard 'Abdullah ibn 'Amr saying: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever lets people hear of his deed, Allah will let the listeners among His creation hear of him on the Day of Resurrection, and He will belittle him and make him insignificant."