It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: My Ummah has been excused for the whispers that arise in their minds; there will be no accountability for them as long as they do not act upon those whispers or express them with their tongues.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 9498