Musnad Ahmad 2507

It was narrated from Ibn 'Abbas (رضي الله عنه), in a report of what the Messenger of Allah (ﷺ) narrated from his Lord: The Messenger of Allah (ﷺ) said: "Your Lord, may He be blessed and exalted, is Merciful. Whoever thinks of a good deed and does not do it, one hasanah will be recorded for him, and if he does it, it will be recorded for him, tenfold up to seven hundredfold, multiplied many times. Whoever thinks of a bad deed and does not do it, one hasanah will be recorded for him, and if he does it, it will be recorded as one sayyi'ah, or Allah will overlook it. No one can fail except one who is doomed to Hell."