I know this sounds like a lesson help, but actually I am talking about a Biblical Era RPG. Green Ronin has put out a role playing game under the D20 system that is set in the Bible era. Called Testament it has ways for players to be Israelites, Hittities, Philistines, and other people’s of the time. It has a distinct working for God flare, but it isn’t preachy. You also don’t have to play as someone who is working for God. If you want to be an idol worshiper there are options for that as well.
I haven’t started to play this game yet but if you are looking to start an outreach roleplaying group this might not be a bad place to start. It would at least be much easier to justify if people start to question why you have a 20 sided die at church.
The only problem that I have with it is that it hasn’t be brought up to 3.5 rules yet which can cause a few minor problems, but nothing that makes the game unplayable. They also have a few adventure modules for it as well. You can check it out at RPGNow.com