I'm not sure of God exists but the incorrect use of the apostrophe in this thread is making me lose the will to live.
At best the existence of God is left vary vague. I would think that a God who required his subjects to worship him in a specific way in order to receive salvation doesn't make that path clear and to the point. Instead, we've got religion that disagree on the path we must take and we have millions who are never even exposed to the idea that the path even exists. A God I can worship would appear in the sky/water/CNN or something and say "Hey, if you want to live eternally here's my rules". Don't tell me he did that through he bible already. That's just a collection of stories a bunch of guys agreed were going to be the truth. It's like interviewing witnesses to a crime, you will get different opinions on what happened from a lot of the people, taking only the ones that match what you think happened and putting them in a book does not make it the divine truth.
In a sentence that length, only if you're Hemmingway. Putting a comma before but so soon in a sentence of that length is akin to using the Oxford comma where the comma is not needed for clarification, but it is a matter of personal preference. Hemmingway would probably have used a full stop. It's all about style dear boy.
The bible also states that Lucifer carried out the tests on Job at the behest of God and that Satan is the "prince of the land and skies" (depending on your version). The bible also has a funky section about a dude being abducted in a space ship (book of Ezekiel) and God needing to test a man by telling him to kill his own son (even though by virtue, there should have been no need - Abraham & Isaac). Just putting that out there because biblical text is absolutely up to interpretation depending on how you want to read it.