In the debate over the existence of God the claim is often made by atheists and agnostics that since the burden of proof is on the one making the positive claim that therefore the burden of proof rests upon the Christian. The unbeliever reasons that because he is not the one positing the claim of someone's existence (in this case, God) that he bears no burden to disprove God's existence since the claim isn't true or can't be known unless it is first proven.
But such reasoning by the unbeliever betrays that he is either unaware of or dishonest about the nature of the debate between the Christian and the atheist.
There's alot that can be said regarding the issue of the burden of proof, so maybe I'll have to divide this up into a few posts. But let me start by saying that if an unbeliever and a Christian do engage in debate over the question of God's existence then it's necessary to do just that: to debate. That involves offering evidence, proofs, reasons, arguments. If the unbeliever shows up to the debate and says that he's not going offer any proof that God does not exist then he concedes the debate to the Christian. It's like saying, "I want to debate but I'm not actually going to debate." If the unbeliever does try to offer proofs for his position then he assumes that he does have a burden of proof, otherwise it wouldn't make any sense for him to debate, and yet atheists do debate. In summary, to put it crassly, either put up or shut up. Neither the Christian nor the atheist want to hold to their respective positions arbitrarily, assuming they want to be rational. I think that even an atheist can follow and agree with this reasoning.
However, the atheist may still want to reply that even though he's not 100% certain whether God exists he still knows that Christianity is wrong or false. Thus, the unbeliever may want to show up to the debate in an attempt to disprove the claims and arguments of the Christian theist while at the same time admitting that he himself hasn't necessarily proven that God does not exist (the problem of the universal negative, which by the way is not a problem for the Christian, but I'll save that for another time). But it is still irrational for the unbeliever to conduct himself in this way. Why? Because when the unbeliever denies the existence of God or claims that there is a lack of compelling evidence to believe in Him the unbeliever presupposes a whole host of positive claims for which, by his own admission, there'd be a burden of proof. The atheist is not at all neutral in the debate over the existence of God.
The key to resolving the disagreement between the Christian and the unbeliever over the issue of the burden of proof lies in understanding the nature of the debate between the two over the question of God's existence. The debate is not merely about one isolated claim, i.e., God exists. Rather, both the Christian and the unbeliever bring to that debate a whole host of presuppositions about the nature of reality, possibility, about ethics, about epistemology, truth, teleology, and so on (Bahnsen often spoke of the "big three": metaphysics, ethics, and epistemology). Both have what Reformed Christians often call a "worldview," a philosophy of life/reality by which they reason and interpret their experiences. Both the atheist and the Christian theist have assumptions about what is acceptable evidence, how much evidence is needed, what is compelling, what can be known by the evidence, and so on. Thus, when the dispute arises over who has the burden of proof, both the Christian and the unbeliever can be found reasoning about that issue in light of their presuppositions, in accordance with their worldview. Therefore, if the Christian and the atheist reason about the question of the burden of proof in a way that is consistent with their worlview they will necessarily end up disagreeing on this matter (logically speaking, that is, though not necessarily psychologically, but I won't go down that rabbit trail). Neither one is neutral on this issue. In fact, if both rightly understood their opponent's position then they ought to know even before they debate that they're going to disagree on the question of the burden of proof.
In my next post (or perhaps two or three posts) I'm going to try and clarify the Christian position on the matter of the burden of proof, offer a way to resolve the dispute with the atheist, and finally to actually resolve the matter by demonstrating that the unbeliever's position, if he is consistent with himself, is irrational, and that to the extent the unbeliever does attempt to shift the burden of proof to the Christian that he actually has to rely upon the truth of Christian worldview, thus proving Christianity from the impossibility of the contrary.
In the end I hope that readers will see that the the question of the burden of proof in the debate over God's existence is actually a great way to prove God's existence and the truth of Christianity.