I'm no scholar, but:—

The first sentence needs to be constructed better, I think...

Something like "The Tree has had a central role, under the Viking Age and in the Protestant North, in the symbolic description of the spiritual — the living and the authentic."

Capitalise your proper nouns or what you want to make into a proper noun; Norse; World Tree; Ragnarok, Christianity; Garden of Eden, etc etc

"This god didn't like this since he foresaw " - 'this' referring to them eating the fruit, but using 'this' twice in the sentence is repetitive. Take out one of them.. Either say "God didn't like this" or "Yahweh didn't like this" or better yet "This god didn't approve of their actions, since he foresaw..."

"The humans had listened to the snakes cleaved tongue" — to the snake's [punctuation]

"they had now knowledge of good and evil" They now had the knowledge

"...which got inspiration from our forefathers observations" ...which had been/were inspired by our forefathers' observations [wording and punctuation]

Oxford's gravel roads [punctuation]

and gave them names. fullstop [punctuation]

I'd look for a summary paragraph to close off the thoughts, just two sentences or so that really enforce the point of the piece, and leave the reader with something to think about. Right now, you're leaving the reader thinking about Tolkein giving names to trees. If that's what you want to leave with people then that's up to you.

Those are my thoughts, for what they're worth.

I'd recommend reading The Elements of Style, it's a small, easy to read book, with such invaluable information.

I'd be interested in reading more things like this, because I am pretty interested in European mythos and the stories of our forefathers.