Volume 8, Book 82, Number 801:
Narrated Abu Huraira:
The Prophet said, “The one who commits an illegal sexual intercourse is not a believer at the time
of committing illegal sexual intercourse and a thief is not a believer at the time of committing theft
and a drinker of alcoholic drink is not a believer at the time of drinking. Yet, (the gate of) repentance
is open thereafter.”