The Arma Christi [General discussion]

[Koen G]

And look what the mitre is paired with on the right-hand side.... a blindfold. So now we know exactly what they represent.

Aah it's the blindfold, of course! I kept thinking about the various clothes and shrouds.
(My knowledge of these things is limited to whatever I can remember from (catholic) primary school
So a quick googling session later, I know that Jesus was blindfolded by the soldiers who bullied him. This was during the chapter of the You are not allowed to view links. Register or Login to view., when he appeared before Caiaphas. 

They were frequently depicted like this:
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Not the best explanation though, I wouldn't add this to the list.