Volume 3, Book 31, Number 125:
Narrated Abu Huraira:
The Prophet said, “Whoever established prayers on the night of Qadr out of sincere faith and hop –
ing for a reward from Allah, then all his previous sins will be forgiven; and whoever fasts in the
month of Ramadan out of sincere faith, and hoping for a reward from Allah, then all his previous
sins will be forgiven.”