Maranatha Et in Arcadia Ego

I had ordered a Book " Maranatha et in Arcadia Ego" well this is a Puzzle Book that needs to be decoded.
Seemed simply enough. Pig-Pen Cipher. I decoded it. Now I am trying to find someone with a little help in the Mythology Part, because this seems to be what most of this book is about, with hidden meanings.
They are giving away One Million Pound prize (Silver)

I need alittle help. I know I probley wont win the prize, this is not to much of a concern for me as it is to Figuare out its meaning. It has to deal with " Hermes" who was by the way " Mercury" and " Tiresias" he had a staff. Hermes had a Staff also. well this staff is the medical symbol staff(Caduceus) we see today. Thats as far as I had gotten. I need info on " Asclepius" He also had a Staff, but his had just one snake wrapped around it. This is the EMS symbol we see today.
Which one came first? The one snake staff or the two snake staff?
Also I have alittle info on Arcadia. This place seems to be like a Paradise. Not a real place. I know there is an Arcadia in Greece but the Original was like " Eden" Correct me if I am wrong. So when I went to the Poussin Painting an looked at this, I seem to think that Poussin was telling us that even in Arcadia( Eden) Death is there. but now I am not to sure.
Also one more thing here, it talks about " Thothmosis" I am thinking this was the Biblical Moses? he was over there in Egypt. ok, anybody with any help?