You can use gods in a game, but not God. You can use priests, monks and religious leader, but you can not use Jesus Christ just like that.
All the games I know that use religion, take a carefull approach towards a religion as we know it. Or at least you can't according to some.
The game that started the debate was this: Eon of Tears

You get to play as mozes and Jezus in this game.

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