What should I do about the recurring evil thoughts that come to my mind, and am I sinful for that, and am I considered offensive to the Messenger of Allah, may Allah bless him and grant him peace, because of what crosses my mind?

"Passing thoughts and obsessions that cross one's mind, over which a person has no control, are forgiven by Allah as long as they are not spoken or acted upon. However, one must not dwell on them, but rather stop them and completely turn away from them. If Satan reaches the point of asking, 'Who created your Lord?' then one should seek refuge in Allah and desist. A person should occupy himself with remembrance [of Allah] and contemplation of what is beneficial. When experiencing intrusive thoughts, one should say, 'I believe in Allah.' The mere occurrence of these thoughts in the mind carries no blame."