Studies indicate that religious and spiritual dimensions are positively related to all forms of mental health, including indicators of subjective well-being and personality factors. It has also been suggested that religious/spiritual well-being might play an important role in the development, course and recovery of mental illness. However, despite such claims, there have been numerous recordings of delusions and hallucinations adopting a religious nature. Furthermore, there is some evidence that religion and spirituality can be harmful for patients with psychosis. Currently, relevant empirical evidence is sparse and more research is needed in order to delineate the role of religious/spiritual issues, as religion and spirituality may be part of the disease as well as part of the cure. Thus patients with a severe mental disorder might use different religiously/spiritually based strategies to cope with their disease effectively. Religion and spirituality were found to protect against addictive behaviours and suicide attempts. Furthermore, religion and spirituality enable the experience of personal growth, and might be considered as important topics within inpatient treatment. Based on empirical results, the question concerning religious/spiritual needs among psychotic patients will be discussed.