"I cannot imagine any reason. I am conscious there are a lot of very upset students at the moment, though."

Rev Caddick said the sermon was inspired by the story of Maximilian Kolbe, a Polish priest who had voluntarily taken the place of another prisoner at Auschwitz who was due to be killed.

He said Maximilian's sacrifice to save the other prisoner's life was reminiscent of the death of Jesus, and he refuted the idea they would ever make a joke about the Holocaust.

An Emmanuel College spokesman said: "We understand that without context this image may have upset people and we apologise for its use in a way that has caused distress. In the service, its use will be explained."

CLARIFICATION: This aricle originally referred to Auschwitz as a "Polish death camp". The camp was in German-occupied Poland and was run and controlled by the occupying forces. We are happy to make this clear.