The W or ‘V V’ symbol is probably the most common single mark to be found as graffiti in churches.
The symbol is often referred to as a ‘Marian mark’ as it has traditionally been associated with the medieval cult of the Virgin Mary, or Maria. The V’s are thought to have once stood for ‘Virgo Virginum’ – Virgin of Virgins or inverted, as M, for Maria, possibly deriving extra significance from having the same meaning whichever way up it was. It is one of the few inscribed marks that occasionally also appear in formal church imagery, including on bench ends and stonework, and often in combination with other known Marian letters (AM, AMR) and symbols.
The use of the W or V V symbol as graffiti is very long lived and is found in churches, domestic buildings and in caves. It seems likely that the medieval religious meaning as an invocation to Mary was lost or changed emphasis over time. It is clear from the common use of the marks around doors, windows and other openings, however, that they continued to have an important protective or apotropaic function.