When is a person considered afflicted with Waswas (obsessive whispering), and is it permissible for him to judge himself as such? What is the nature of the Waswas that does not lead to divorce, even if the person afflicted with it utters the words of divorce, as stated in the fatwa of Sheikh Ibn 'Uthaymin?

Wawaswesah (obsessive doubt/whispers) is an illness resulting from the devil's dominion. Among its forms is wawaswesah regarding divorce, where the person suffering from it (al-Mawaswis) believes he has divorced his wife and remains in confusion and doubt. Another form is wawaswesah regarding purity, where one repeats ablution (wudu') believing he has not washed one of his limbs. The cure for wawaswesah is to strengthen one's faith and not yield to it.