It was narrated from Ibn ‘Abbas (رضي الله عنه), that:

The Prophet (ﷺ) said, in a report in which he narrated from his Lord: “Allah decreed hasanat and sayyi’at. Whoever thinks of a good deed and does not do it, Allah records it with Him as one complete hasanah, and if he does it, Allah records It as ten (hasanats), up to seven hundred or many times more – or as much as Allah wills to multiply it. Whoever thinks of a bad deed and does not do it, Allah records it with Him as one complete hasanah, and if he does it Allah records it as one sayyi’at.”