Church leaders have condemned a course in paranormal studies at Cirencester College as "potentially dangerous".
The five two-hour evening lectures, conducted by medium Sharon Gound, begin this week.
The archdeacon of Cheltenham, the Venerable Hedley Ringrose, said he feared "vulnerable" students may not be able to cope with the experience.
But Ms Gound said: "This is a fabulous opportunity to clear up ignorance and misunderstanding about the paranormal."
The course involves Ms Gound contacting her "spirit guides" to whom students can pose questions.
But the Venerable Ringrose said: "There are many bereaved people who are at a vulnerable stage in their life where they might not be able to handle something like this.
"My message to the college would be to be aware that the Christian churches offer ministry to those who are bereaved - not through contact with those they have lost - but pastorally."
The college said its role was to open up educational opportunities.