This will not end well cause of religion being involved.
Many are going to ask 'lulz my god or urs'
You must become a Master Baiter if you want to want to master the One-eyed Fish of the Dark Caverns!
From a logical point of view, God is a "divine being". He would either be a priest or a paladin.
My dad once told me that aslong as religion existed, even I could make my own fantasy buddys
Why would the only person with power playing the game pick the only class with no power?
Considering a usual trait of God is omnipotence, I would say he would play a few characters of every class and 25 man raid with himself on them.
If jesus did he's be shaman.
What.. he walks on water and heals the sick.
pppsssh puny gods, Odin and his sons would all choose warriors, your god would choose a paladin n00b