There is no onus of proof on atheists to disprove god…
However, if an atheist chooses to assert that there are no gods, and in particular chooses to assert that there is no personal intervening god with whom humans can have relationships, that atheist can reasonably argue that such an assertion is proportionate to the best currently available evidence.
Very nicely written, and recommended reading.
And by the way, one of my favorite answers to that argument is simply to rephrase it. By saying that atheists cannot prove that God does not exist, the believer is making the implicit claim that there is no argument that can disprove God’s existence. They cannot prove the non-existence of this incontrovertible proof against God, however, and therefore by their own logic atheists are justified in believing that such an argument does exist, even if the unbeliever themselves might not happen to know it. Consequently the best outcome the believer can hope for is a kind of solipsist agnosticism that reduces Christian “eternal truth” into merely a subjective fantasy.
How would you answer it?