I'll summarize what is said by "Accademia della Crusca" which is another respectable source to find the meaning of Italian words. They basically say that some word spreaded according to geographical locations or different way of comunications. To express the concept of "in this moment" ("in questo momento") Italian poets have substituted the word "nunc" from Latin, with some variants like "ora, mo, adesso". As said, these abbreviations are used differently in different regions and could be combined. Some special form were lucky enough to be used nowadays like synonymous of "now" such in the cases "mo ora", "or ora". Thus, their usage depends on a multitude of things. Personally if I would translate in English the two sentences they would be:
- "Now earth was corrupted in front of God";
- "Meanwhile he said to them these things, one understood about the synagogue, close to him, bowed in front of him and said: 'my my daughter is died right now (right in this moment); but come here, put your hand on her and she'll live".
The last sentence lets understand that the moment is very close, so you could still see what happened. Therefore the repetition "or ora" is used to reinforce the concept of "now". The first phrase instead is more generic, "now" could refer to "from now on".
I hope this is useful and I apologize if I made some mistakes in English.
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