Sahih Muslim, Chapter: Faith (Kitab Al Iman)

that the Messenger of Allah (may peace be upon him) observed: He who intended to do good, but did not do it, one good was recorded for him, and he who intended to do good and also did it, ten to seven hundred good deeds were recorded for him. And he who intended evil, but did not commit it, no entry was made against his name, but if he committed that, it was recorded.