It's about having been hurt in the past. When you fall in love, you give yourself up to the other person. You make yourself completely vulnerable at the other person's expense. He has been hurt in the past, and is deciding "screw it, I love this person too much to care about how I got hurt in the past." To me, it sounds like there is a bit of hesitance in the song, like he somehow knows that he will be hurt again, but he is too smitten to care, so he hopes for the best and takes down all of his walls.
It's about having been hurt in the past. When you fall in love, you give yourself up to the other person. You make yourself completely vulnerable at the other person's expense. He has been hurt in the past, and is deciding "screw it, I love this person too much to care about how I got hurt in the past." To me, it sounds like there is a bit of hesitance in the song, like he somehow knows that he will be hurt again, but he is too smitten to care, so he hopes for the best and takes down all of his walls.