I'm swiftly gaining sympathy for a position a Jewish friend of mine holds. The idea is that for man to have free will, creation must be such that someone could plausibly deny the existence of a creator.
Blaise Pascal wrote quite a bit on it. The idea that there is enough proof of God's existence to know that He exists... But only if you look. That at that same time if you don't look, you could easily deny God's existence. I like your Jewish friends thinking.