Writing/symbol at Thunderbolt's hideout?

Anyone know if this is supposed to mean something? Or is it just some more random graffiti?
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Swifty wrote:Yes that is Christian graffiti, showing the superimposed Greek letters CHI RHO, which are the first two letters of Christ.
It is a very early Christian symbol. Also explains the crosses.
That is the white symbology in ?chalk. The underlying older yellow brown lines are unknown to me , so they must be some pagan script!
It almost looks like the Christian is trying to perform a "counterspell" on the earlier runes. Certainly looks like two generations of writing.
Yours truly
ROBERT LANGDON![]()
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GPSGuided wrote:Not to be visited after nightfall!![]()
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