I think this song is about his job, he is a rock star, when he says "When I hear the sounds of the trumpet call ", he is saying that he has to go, it's his job, he's going on a tour, and for the first time he is far from home for a long time, cuz in the end life is a war, and this is what he's got to do, for himself, for his family. And when he says "Promise that you always will
Keep candles lit on the windowsill ", I think he is remembering she said that no matter what happens she will keep their love flame burning.
I think this song is about his job, he is a rock star, when he says "When I hear the sounds of the trumpet call ", he is saying that he has to go, it's his job, he's going on a tour, and for the first time he is far from home for a long time, cuz in the end life is a war, and this is what he's got to do, for himself, for his family. And when he says "Promise that you always will Keep candles lit on the windowsill ", I think he is remembering she said that no matter what happens she will keep their love flame burning.