It's a very interesting and captivating part of hystory.
The symbols that remember Christianity in Salerno come from II -III centuries. The Roman Empire was probably not powerful in this period too, because citizens can create christian church in a public building after one of floods. But the cristianization story was not so simple. Because there were many pagan temples and statues bounded to antient greek and latin rituals and there were many persons that believed those Gods. Some centuries needed to pass to christianity.
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What I like is to discover symbols of the christianity that we don't remember. And the best place to do it is Salerno.
For example, the entrances in the churches (Dom) were circular like this (not all, clear)
Every person in the Middle Ages knew it:
You rise in the house of God, not go up the steps.
And when you are for the entrance door you see
lions that meet you. One is female, other is male.
Why?
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But the powerful mother-church loves your kids like the lioness here for you nurses her cub.
So the unliterate persons of the Middle Ages were prepared by symbols befor they decide to enter their temple.
A sort of the today publicity, mmmm?
Next time next symbols.