Richard Taylor’s book How to Read a Church, first published in 2004, has been enjoying a boost in sales since the start of his BBC TV series, which concludes on Wednesday.

While the TV programmes are organised historically, in chronological order, his book is designed for practical use by people who like visiting churches, but are not quite sure what to look for. There’s plenty of interest, even if you are more knowledgeable.

He disagrees with the common assumption that the images were needed because most of the early congregations were illiterate, arguing that most of them pre-suppose a considerable knowledge of bible stories and their symbols.

One of the first clues for the casual visitor is the story of the saint who gives the church its name, and Taylor includes a list of saints and their symbols.

The South Door at St Mary’s Church in Iffley, for example, appears in the book as an example of how the rose is used as a symbol of purity, associated with the Virgin Mary. The finely carved figures on this medieval marvel include centaurs, a merman, a kin, Samson and the lion, plus animals biting their own tails.

How To Read A Church is published by Rider Press in a glossy colour version at £25. There’s also a cheaper version at £10, or a pocket guide, £12.99.