Speaking generally, since the time of Freud, psychotherapy (with the notable exception of transpersonal modalities) has worked hard to establish itself as a quasi-scientific discipline.
Consequently most therapists have been trained and encouraged to distance themselves from discourses which might, loosely, be defined as "spiritual". Even though that attitude is now is changing rapidly, the fact is that those seeking help with issues of spiritual confusion, crisis or conflict often struggle to find open-minded and unprejudiced support in a predominantly secular theoretical environment.
In my view, however, Existential Psychotherapy, by addressing life's deepest questions with the emphasis it places on the meaning of freedom, mortality, anxiety and autonomy, inevitably invites an exploration of the spiritual (This approach, however, is categorically not to be confused with what is now termed "faith-based counselling" in which the therapeutic relationship is informed and directed by a rigid and sometimes dogmatic system of beliefs and practices and in which the counsellor her or himself is frequently neither adequately trained nor equipped for clinical work).
In terms of whatever beliefs I myself may or may not hold, I endeavour to remain neutral at all times in my work with clients whose issues touch upon or are predominantly focused upon spiritual issues. My role is to provide a safe, supportive and non-judgemental space in which clients of any faith, or none, any belief system or combination thereof can feel secure and confident enough to explore and confront their issues both spiritual and secular.