Well, let's break it down. You're a doctor, I'm a doctor. Either God is causing these diseases we see every day, or else he can't do anything to stop them. This voice is from a skeptical colleague I used to make rounds with in the hospital, a confirmed atheist. But he would press the point.
Reality is reality.
God can't survive any kind of objective test. But we all know that. Some of us just choose not to keep on fooling ourselves. On one level he was right. Materialist arguments against God remain powerful because they are based on facts, but they fall apart once you dive deeper than the material world.