It is mainly used for the Sacrament of Penance (also known as confession) in the Roman Catholic Church, but similar arrangements exist in some Anglo-Catholic and Lutheran churches.
In comparing a doctor's attitude to that of the priest in the confessional, Dr Baker is referring to the rules of confidentiality which doctors adhere to. The importance of confidentiality is highlighted in the Hippocratic Oath, an oath historically taken by doctors, swearing that they will uphold certain ethical guidelines in their work. However, until 2000, there was no statutory duty of confidentiality in the United Kingdom. Issues of confidentiality in medicine are extremely complex, and situations will arise where doctors may feel it appropriate to breach confidentiality, or may be legally obliged to do so.