http://mentalhealthdaily.com/2015/04/29/types-of-delusions-extensive-list-of-themes/

What are delusions?

In the earliest days of psychology, diagnostic criteria for delusions were developed by Karl Jaspers. Jaspers wrote an essay called “General Psychopathology” in 1910 that discussed delusions and various aspects of jealousy. He had specific criteria that included three key descriptors including: certainty (conviction), incorrigibility (unchangeable), and impossibility of content (implausible).

Certainty: Individuals that hold delusions are certain in their beliefs; they believe with 100% conviction that they are real, despite significant logical evidence to the contrary.

Incorrigibility: Those with delusions will not update their false beliefs even if presented with overwhelming logical evidence suggesting that the opposite is true. Despite scientific evidence to suggest that their way of thinking is flawed, they aren’t able to escape their deluded perception.

Impossibility: The delusion that a person holds is not only untrue, but generally impossible or highly implausible to be true. Some of the delusions may not only seem like an obvious impossibility, but they may seem highly bizarre.

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Religious delusions: These are considered delusions that have a religious or spiritual basis. It is common for religious delusions to be connected to delusions of grandeur (e.g. a person believes they were “chosen” by a deity to become famous). These may also be connected to delusions of control (e.g. that a God is hearing their thoughts), and delusions of guilt or sin (e.g. that they should go to “Hell” for a tornado that occurred in Kansas). It should be noted that beliefs that are considered the norm for a particular religion or culture are not regarded as delusions.

Delusions with religious content (DRC) are associated with poorer clinical outcomes and dangerousness.1-6 Most mental health professionals will encounter patients with DRC because this type of delusion is relatively common in patients with symptoms of mania or psychosis. For example, in a study of 193 inpatients with schizophrenia, 24% had religious delusions.
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Dangerousness in patients with DRC can manifest as self-harm or harm to others. Extreme examples include self-inflicted enucleation of the eye and autocastration. In a review of 9 cases of severe ocular self-injury, 4 patients had DRC.3 Genital self-mutilation associated with DRC is rare, but several cases of psychotic men who performed autocastration based on a literal, erroneous interpretation of a passage in the Bible (Matthew 19:12) have been reported.4,5 Patients with DRC have committed rape and murder because they believed they were the antichrist.6