The character of The Vicar of Bray appears in a traditional English folk song with that title.

The eponymous vicar was the clergyman of the parish of Bray on Thames, Berkshire. The lyrics recount his adaptability (some would say amorality) in embracing whichever form of liturgy, Protestant or Catholic, was favoured by the monarch of the day in order to retain his position.

The story has its origins in the person of a 16th century cleric called Simon Alwyn, but the most frequently sung words refer to 17th century monarchs.

In recent years the phrase has been used as the name for a hypothesis as to the adaptive benefit that sexual reproduction offers to a species in the theory of evolution. This theory points out that the offspring of a population of sexually reproducing individuals will show a more varied selection of phenotypes and that they will therefore be more likely to produce a strain that can survive a change in the ecology of the environment in which they live. A mathematized version of this theory was accepted by most biologists as being one of the most important reasons for the prevalence of sexual reproduction in the natural world until the implicit group selectionist character of the argument was re-examined in the course of the Williams Revolution.