What is the ruling on one who yields to a whisper that calls to other than Allah, then denies it with his tongue and heart?

Intrusive thoughts have no effect as long as the person does not speak them, and his disapproval of them indicates his lack of conviction in them. It has been authentically narrated in the Hadith that Allah has forgiven the Ummah for the whisperings of the breasts, as long as they are not acted upon or spoken.