Try this - rest quietly, letting the body sink into the support of the surface it's resting on, and simply observe the breath for a bit. After a while, take a few smooth conscious out-breaths with a softly open mouth (somewhere between fogging a mirror and a sigh). Let the exhale be long and gently compressive of the whole torso, but not to the point of tension or strain. After each full exhale, pause and let yourself be "in-spired"...
Our quote is from Laurence Binyon, an English poet and playwright who survived WWI. Instead of thinking it through, try letting it wash over your body and communicate with your cells as you breathe: "We too should make ourselves empty, that the great soul of the Universe may fill us with its breath."