'Abdullah bin 'Abbas (May Allah be pleased with them) reported:
Messenger of Allah (ﷺ) said that Allah, the Glorious, said: "Verily, Allah (SWT) has ordered that the good and the bad deeds be written down. Then He explained it clearly how (to write): He who intends to do a good deed but he does not do it, then Allah records it for him as a full good deed, but if he carries out his intention, then Allah the Exalted, writes it down for him as from ten to seven hundred folds, and even more. But if he intends to do an evil act and has not done it, then Allah writes it down with Him as a full good deed, but if he intends it and has done it, Allah writes it down as one bad deed".[Al-Bukhari and Muslim].
Arabic/English book reference: Book 1, Hadith 11