In contrast to the agnostic approach, we have Richard Dawkins, the well known athiest, who has a lot to say about and to Christians.
For example, he says that they are already on the road leading to athiesm; specifically, Christians are but one step away from being God-free: They have attacked polytheism, declaring all the other "Gods" of the word religions to be false and non-existent. A belief system that eradicates 99.9999% of "Gods". That's impressive. Now, all Christians have to do is take one further step and declare that their one "true" God doesn't exist either. Step forward please.