QUIET days are in vogue; it is what spiritual people do. But might some retreat-house quiet day be the last thing you need?

On retreat, the priest met with me for a one-to-one. Early in our encounter, he told me that he had led a retreat at this venue. "It was a retreat on stress reduction," he said, although he was extremely stressed now. But there was more. He also told me that he led spiritual quiet days - he had done so for years, and was reckoned a safe pair of hands in the spirituality business.

But what became apparent as we talked was this: he did not know himself to any great degree. He did not understand the forces at work within him: forces that shaped so much of his doing and feeling. And here, on retreat, these unknown forces were screaming loudly to be heard. He had a spiritual awareness, but little psychological self-knowledge, and was damaged by this lack. Relationships around him were not all they might be.

I do not denigrate spiritual awareness. Jung believed that he was successful with clients only when they possessed or developed some sort of spiritual dimension in their lives, and I can understand that. On a good day, spirituality creates a sense of space in a life, and a sense of holding - both helpful in psychological adventuring. But we will not mistake spiritual and psychological awareness as being one and the same, because they are not: they are different.

People can inhabit spiritual events for years (even lead spiritual events for years) and know next to nothing about their own inner workings. They have heard much about God's inner workings; but it is necessary that, along the way, they discover more about their own. St Paul would have been a greater writer had he understood himself a little better.

If a compulsive sense of guilt is yours, allied to a fear of blame, then Paul's gospel will speak to you with peculiar power. But if not - if you struggle to know what to do with the confession, for instance - then you may find it harder to engage with his excited words about justification. There are many gospels.

Spirituality can even get in the way of awareness by making a virtue of "calm". On a retreat recently, one disturbed priest, overwhelmed by certain relationships, told me how she had just wanted "to come away for some quiet time with God".

I said that this was a quiet time with God - quiet, but not calm. Here was time in which she was learning helpful truths about herself. What could be more godly than that? Quiet days that are determinedly "quiet" may be the last thing someone needs.

Spirituality and psychology are related, but different; they are sister and brother, with lives of their own.

Simon Parke is the author of One-Minute Meditation (White Crow, January 2014).