Locks and keys are instruments of the Devil.

This is a detail of a 12th century Anastasis (depiction of the Resurrection) in St.Mark's, Venice.
The alleged Messiah "hath broken the gates of brass and smitten the bars of iron asunder"
(as is written in the Apocryphal Gospel of Nicodemus).
The handsome mauve chap with inviting beard and buttocks is Satan,
alias Lucifer, who dared to challenge the Führer (or First Secretary) of Heaven.
He is being trampled on by Mr Goody-Goody who has nail-holes in his feet.
I like to think that locks and keys and chains are entirely devilish.
The rich and the bourgeois, obsessed with 'security', are...
entirely devilish.