Machen served as a YMCA volunteer during the first world war. A lot of his time was taken up with serving tea and hot chocolate to the soldiers:
One German fellow said when I gave him the chocolate that it was “wie bei der Mutter.” It would have taken a harder heart than mine to keep from being touched by that. By the way, along with the hatred and bitterness incidental to war, there are some examples of the other thing which like the fair lilies in swampy ground are all the more beautiful because of the contrast with the unlikely soil in which they grow. Thus at one of the dressing stations near the front, I saw an American wounded soldier deliberately take off his overcoat and give it to a wounded German who was suffering a lot worse than he. When one reflects what that little act meant—the long cold hours of rain and damp along the way to the rear and the interminable waits— it becomes clear that magnanimity has not altogether perished from the earth.