I recently watched a debate, posted in full on youtube, between Christopher Hitchens and four well-known Christian apologists. Here's the link: http://www.youtube.com/watch?v=S0aoH5QJO0s&feature=related
Much of the debate centered around the, I think, rather puerile debate of theodicy, or the problem of evil. When entering into debate with believers, granted I don't know them, I use this problem as a sort of litmus test to comprehend the sophistication of the other person. In other words, if they cannot give the time-honored Christian answer to the problem of theodicy, then I know I'm dealing with someone who hasn't thought much about their beliefs: a true specimen of the sickness of faith (for faith, rather than belief in things unseen as many attempt to define it, is rather for most, in praxis, blind belief in their father's religion). The proper Christian answer is very simple: evil exists in the world because God wants us to love him, love is only love if it is given, one cannot give anything without free will, hence God created man with free will knowing that it would result in evil. Sadly, much of this debate, despite the intellectual rigor of its participants, centered around this elementary problem. And in the elementary aspects of this problem. Because I think there is much more to be discussed that is not often discussed about it.
Firstly: is it not possible to imagine humans with free-will that do not commit such egregious acts as child rape (see, for example, the Catholic church), or brutal murder, or genocide, or chemical warfare? If it is possible for us (lowly sinful humans that we are) to imagine it, then it is certainly possible for an omnipotent creator to make this possibility an actuality.
Secondly: the believer must establish not only that evil is the unwelcome result of free-will, as they have easily done for centuries to answer the problem, but that ultimately more good comes of free-will than evil. That is to say, if the good does not outweigh, so to speak, the evil in the world, and in human history, then God has knowingly created an evil world. It seems that one could easily make the case, at our particular juncture in history after Nazism, the Gulag, Darfur, the Khmer Rouge, Apartheid, Rwanda, the world wars, Bolivia, the Armenian genocide, American slavery (and other slaveries), etc., etc., etc., that more evil has come of the human species than good (not to mention the evil we perpetrate upon other species through factory farming, habitat loss, genetic modification, etc., and upon the planet that supports us). If this is the case, then it is simply incompatible with the Christian concept of an all-loving, all-merciful God. It is compatible with a narcissistic sociopath of a God that loves and cares only about himself and his own pleasure and that would watch silently the suffering of millions that a few might choose to love him. But not with the Christian God. Unfortunately, though any Christian that has thought a modicum about their faith can offer the elementary and time-tested response to the problem of theodicy, they are not often challenged further as they should be.