I didn't bother reading through all the comments, but most of you are way off. This song is packed with relgious language, specifically Christian, and even more specifically, Catholic terms. In earlier ages it was more common, but even today, a monk will wear uncomfortable clothing to do penance, a way to "take up your cross, and follow me" in the words of Jesus. A hair shirt was extremely rough, irritating material worn against the skin underneath one's normal clothes. The song is about struggling with a religious upbringing, temptation to abandon its requirements, etc., reconciling that with falling in love. It's a coming of age song. That's how I hear it anyway. But good songs tend to mirror our own values and reflect them back on us.
I didn't bother reading through all the comments, but most of you are way off. This song is packed with relgious language, specifically Christian, and even more specifically, Catholic terms. In earlier ages it was more common, but even today, a monk will wear uncomfortable clothing to do penance, a way to "take up your cross, and follow me" in the words of Jesus. A hair shirt was extremely rough, irritating material worn against the skin underneath one's normal clothes. The song is about struggling with a religious upbringing, temptation to abandon its requirements, etc., reconciling that with falling in love. It's a coming of age song. That's how I hear it anyway. But good songs tend to mirror our own values and reflect them back on us.