Everywhere around us there are images and symbols, not made by men, but by God himself: trees, sky, mountains. The beauty, complexity and marvel of nature form the image of who He is and what He is. But man wants more and more and gets caught in symbols and rituals that give him a sense of being closer to God in that way, and that isn't always the case. Naturally there are images that have a purpose, in painting for instance. Images from the New Testament, or from Christ and the apostles. I think they are all fine. In the Middle Ages artists like Bouts or Bosch used there talents to convey the message of the Bible to people who probably couldn't even read or write. And that's what it's all about, go around and let people know about Him.