If a person thinks of doing a good deed it will be recorded for him, and if he thinks of doing a bad deed it will not be recorded for him Sahih Muslim 131 b
Arabic hadith text
وَحَدَّثَنَا يَحْيَى بْنُ يَحْيَى، حَدَّثَنَا جَعْفَرُ بْنُ سُلَيْمَانَ، عَنِ الْجَعْدِ أَبِي عُثْمَانَ، فِي هَذَا الإِسْنَادِ بِمَعْنَى حَدِيثِ عَبْدِ الْوَارِثِ . وَزَادَ " وَمَحَاهَا اللَّهُ وَلاَ يَهْلِكُ عَلَى اللَّهِ إِلاَّ هَالِكٌ
Translation
This hadith has been narrated with another chain of transmitters with the addition of these words
Allah would even wipe out (the evil committed by a man) and Allah does not put to destruction anyone except he who is doomed to destruction.