Penny Parsons, 46, claims she was forced against her will into teaching Islam to a class of 12 Muslim students because Josiah Mason college in Birmingham had failed to recruit a suitable teacher for two years.
Despite her protests, she was made to teach the subject with little preparation or adequate materials and was told by the principal: "You will teach what I want you to teach."
Mrs Parsons, who had taught caring and nursery nursing at the college since 1993, told Birmingham employment tribunal that she had been approached by her senior manager, Paul Yeo, in June 2002 and asked if she would teach religious studies from an Islamic perspective in the new term.
She told the committee she was "speechless" at the request, saying that although she had a degree in religious studies and had taught the subject to 11 to 14-year-olds 20 years ago her knowledge was out-of-date and insufficient.
She said: "I was shocked and dumbfounded that I should be asked to teach this when I was under pressure in my own department.
"Religious studies is a very personal subject to teach from an Islamic faith perspective. I had no knowledge and no training. I had only ever taught from a Christian perspective and was concerned at teaching Islam to Muslims."
A meeting was arranged to discuss the proposal and, despite her protests, principal Chris Grayson told her: "You are contracted as a teacher and you will teach what I want you to teach."
The committee heard that Mr Grayson told her: "If this was in industry they would be wetting themselves with laughter."
Mrs Parsons, representing herself, said two books had arrived just three days before the course was about to commence, but that they were not on the reading list.
She taught three lessons in September 2002, but was signed off sick the following month until she resigned at the end of the year.
"I found the experience stressful and demoralising - my teaching abilities had been seriously compromised," said Mrs Parsons.
David Faulkner, for the respondent, said it was not unreasonable for someone with a religious studies degree to teach it, and that her contract stated she would be called to perform other duties.
"Subjects may well be assigned to you even though what you are required to teach may not fall into your specialism," he said. The hearing was adjourned until September.