I feel this song is saying that we need to fight our own fights and over come are challenges and hardships that we have in life. Mealine says "no one else can fight this fight" she stated that we on our own and with a little bit of help can over come these challenges. She represents Goliath as all of her problems and she says that "you are no bigger than me" stating she can over come all of her problems. "Just like I know you've got something inside of you" she is stating we need to be our own hero.