سنن ابن ماجه

It was narrated from Abu Hurairah that the Messenger of Allah (ﷺ) said: “The adulterer, at the time he is committing adultery, is not a believer; (the wine drinker) at the time he is drinking, is not a believer; the thief, at the time he is stealing, is not a believer; the plunderer, at the time he is plundering with the people looking on, is not a believer.”