I most of the time abuse and say bad words to satan. When he brings some bad thoughts. Is this permissible?
Firstly, you shouldn't get into a habit of saying bad words in any case since the Prophet (SAW) said:
"The believer is not one who curses." (Jami al-Tirmidhi)
Secondly, Allah told us in the Quran what to do when Shaitan gives us bad thoughts:
And if there comes to you from Satan an evil suggestion, then seek refuge in Allah . Indeed, He is the Hearing, the Knowing. (Quran 41:36)
Seeking refuge in Allah is to say: أعوذُ بِٱللَّهِ مِنَ ٱلشَّيۡطَٰنِ ٱلرَّجِيمِ (auzubillah minashaitan nirrajeem). "I seek refuge in Allah from Satan the outcast."
Remember, Shaitan is our enemy. He will only become gleeful and happy at us cursing him. It was narrated in a hadith that:
A man said: I was riding on a mount behind the prophet (May peace be upon him). It stumbled. Thereupon I said, "May Shaitan perish!"
He said, "Do not say 'may Shaitan perish' because when you say that, he will swell so much so that he will be like a house, and say, 'That was by my power'. Instead say 'Bismillah (In the name of Allah)' because when you say that, he will diminish so much so that he will be like a fly." (Sunan Abi Dawud)
So, when Shaitan whispers something to you, seek refuge in Allah. If something bad happens to you, say "Bismillah." If you curse Shaitan, he will only become proud of himself and happy.
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