Emunah U’Bitachon 1:3

A sight that shakes the wise mind: Man is built so as to be able to ingest food, to digest it and to chemically divide it into different substances. Each substance is distributed to the appropriate place – places which we know about because of the wisdom that man has been graced with: The stomach, the liver, the gall-bladder, the spleen, the kidneys, the intestines, the urinary tract, the heart and the brain. Each organ has a unique purpose and they all work together with astonishing speed to continuously refine the blood. They establish the correct proportion of white to red blood cells necessary to keep this machine – which we call man – alive. In addition, they calibrate the precise amount of blood glucose, and many other minutely measured substances. Man, foolish of heart, is not aware of the vast armies which constantly guard him, working without rest so that he remains living!

It is engaging to study the wisdom of the relationship between living beings and the earth's atmosphere, composed of oxygen and carbon. To act as a buffer between man and the atmosphere, the lungs – all seven¹ of its chambers – were gifted with the power to breathe; to extract the oxygen and sate the thirst of one's flesh, blood, bones and tendons. It ranks high amongst those soldiers who battle to keep man alive!

1. Modern medicine divides the lungs into five chambers.