Stein ^{Reference Stein1} raises an interesting and important question – that of differential diagnosis between spiritual experiences and psychotic disorders with religious content – when he shows that Ezekiel, as described in the Old Testament, has experiences that might be interpreted as first-rank symptoms. In addition to the religious implications of making such a diagnosis for the prophet (and possibly other spiritual leaders), there are critical implications for the evaluation and conduct of people that seek our clinical care with similar experiences.

We have conducted research on the relationship between spiritual experiences and psychotic and/or dissociative symptoms. A sample of spiritist mediums in São Paulo, Brazil, reported on average four first-rank symptoms, the same number as Ezekiel. However, the number of symptoms was not correlated to other markers of mental disorders such as scores on the Social Adjustment Scale–Self-Report (SAS–SR), Self-Reporting Psychiatric Screening Questionnaire (SRQ), and history of childhood abuse. Despite showing a high level of what could be interpreted as psychotic and/or dissociative symptoms, the total sample of 115 mediums had a high socioeducational level, a low prevalence of mental disorders and were socially well adjusted. ^{Reference Moreira-Almeida, Neto and Cardeña2,Reference Moreira-Almeida, Lotufo Neto and Greyson3}

There is an increasing literature showing a high prevalence of psychotic and dissociative symptoms in the general population. However, most of our knowledge of those experiences is based on clinical, often hospitalised, samples. Those and other studies indicate the necessity of being cautious when analysing the clinical significance of anomalous experiences emerging in non-clinical contexts, especially since our knowledge about these experiences is based on clinical samples. It seems that these psychotic or dissociative experiences are not necessarily symptoms of mental disorders. (Similarly, certain medical symptoms such as shortness of breath and tachycardia may be pathological in some circumstances and physiological in others.)

Certain additional features may suggest a non-pathological basis for the experience: lack of suffering or functional impairment, compatibility with the patient's cultural background, absence of comorbidities, control over the experience, and personal growth over time. These criteria are useful pointers, but there is a lack of well-controlled studies. ^{Reference Menezes Junior and Moreira-Almeida4}

Experiences like those of Ezekiel have had an important role in the Greek, Jewish and Christian roots of Western society, and in our time they are prevalent in spiritual groups such as those related to spiritism, channelling, Pentecostalism and the Catholic charismatic movement.

Research to clarify our understanding of this aspect of human experience will not only enlarge our knowledge of human nature but also improve the cultural sensitivity and effectiveness of our clinical practice.