What is the ruling on obsessive thoughts concerning creed and the horrific images that come to mind? Is a person held accountable for them? Is there sin upon a person if they momentarily indulge in them or think about them? Is the sweat of an apostate or what they touch considered impure? And are good deeds nullified if a person leaves Islam and then prays?

Worrying (waswasah) is one of the worst ailments that corrupt both one's religion and worldly life. Those afflicted by it must strive against themselves to abandon and ignore it. All worries, whether concerning acts of worship or creed, must be ignored. No matter how much Satan whispers about matters of creed, do not pay attention to his whispers, for he wishes to spoil your life. Seek refuge in Allah from his evil, and do not concern yourself with the thoughts he casts into your heart. Know that the occurrence of these thoughts does not harm you, and you are still within the fold of Islam. Therefore, do not perform ghusl (ritual bath) if these worries come to you, because you have not left the fold of Islam, and your ghusl would be giving in to them. Rather, completely ignore them until Allah removes them. Do the same with worries concerning acts of worship. No matter how much Satan whispers to you that you forgot something in prayer, ablution, or ghusl, or that you were afflicted by impurity, do not pay attention and proceed with your acts of worship. There is no cure for what you are suffering from except complete disregard. You must repent to Allah for combining prayers if it is not permissible, as this is due to giving in to worries. If you act upon what you have been advised regarding ignoring worries, you will be able to perform your acts of worship normally.