I think it would mean a place where it is safe to feel the discomfort. Some therapists,as far as I have read, think them comforting or resolving the discomfort is a not a good plan (I think this varies from therapist to therapist or type of therapy) because the plan is enough discomfort will prompt the client to decide to change to resolve the discomfort. I would not stay with a therapist I thought was trying to punish me by intentionally inflicting discomfort on me. And I don't think the therapist has the ability to comfort me.