Theists: What is the most compelling argument you have heard for Atheism?

[SteveII]

1. No, it really doesn't. Christians claim these events were supernatural (not-natural) in cause. Since the supernatural cannot be examined by science (by definition), it cannot comment on the cause. It can only describe the effect. 
2. I believe my religion is more evidenced, more plausible, and better describes the real world than others. It does not matter (nor concern me) that you cannot distinguish between them. 
3. Very original and sophisticated arguments. My faith has been shaken.
4. Yes. That is the reasoning I use and it can easily be applied to Thor. Good job at zeroing in on the issues.

If science can't test and falsify it why the fuck should it be assumed? Because you like it? [1] Again, so what, Muslims cant test and falsify Allah. Jews cant test and falsify Yahweh. [2]

I have a giant invisible pink unicorn whom magically makes me truck loads of ice cream that suddenly appear in front of me upon praying to it. Now, that would be a claim beyond nature. But since you cant test and falsify that claim we have to assume it is true by default? Bullshit.[3]

I don't play "if ifs and buts were candy and nuts".... And especially way after the fact. That was then and this is now. If you insist on being stuck in bronze age superstition, again, that is your baggage, but don't expect me to take it seriously.[4]

1. Because I am convinced of the evidence for my belief. 
2. We can examine all religious belief systems for evidence, internal consistency, and how well it explains reality, and compare them to each other. 
3. Sophisticated rebuttal. How many people have seen the unicorn? Did they spend 3 years with it? Did it teach them things that made sense on a level not considered before? Did it perform miracles, die on a cross, and then rise again? Did it then spend another 40 days making appearances and talking to people? Did the people that it spoke to, in turn go out and put into practice what the unicorn instructed all over the known world--often at great personal costs? Do the people that follow these instructions testify of internal changes that were promised? Has this been going on for millennium? Are there over 2 billion people that believe that all these things happened in this order? If not, you are comparing apples to oranges. 
4. You have such a simplistic picture in your head about what you are arguing about and therefore you think your objections carry some intellectual weight. The picture is wrong and your objections are simplistic and mundane. You seem to be just another angry New Atheist that thinks their ideology is something special--it's not--just recycled, philosophically bankrupt opinion with some anger thrown in.