Still in Madison

Still in Madison, and feeling a bit tired. I have an idea for a blog topic, but since I am too tired to write about it, I thought that I would just leave it as a question, then fill in my ideas tomorrow.

At my church we have some amazing stained glass. The Prodigal Son is depicted. So is Jesus. However, my favorite two windows are the one depicting Peter and Paul. Peter and Paul are the two most influential fathers of Christianity whose names aren't "Jesus". In these windows these two giants of faith look distinguished and wise. These are worthy depictions of two strong and heroic men. The actual pictures of them don't really interest me though, it is what else is on their windows. Peter has a rooster on his window, an illusion to his three denials of Jesus before the coming of morning. Paul has three scales (like that of a lizard) on his window, representing the scales that fell from his eyes when his Jesus caused blindness was healed.

Why? Why do these windows depict the most famous failing of these men? Why choose to display Peter's most cowardice moment? Why show Paul's spiritual blindness?

Why are those images so compelling?

Please respond.