"<p>I, for example, although I was already a grown man, got into swimming and tennis. I particularly took a liking to tennis when I was in my forties; it is the only humanistic sport; man against man, with all the strength one can muster, but there is always a distance between the combatants, they do not touch. Just as Luther never saw Erasmus, with whom he dueled for a lifetime. And swimming, how good it was, especially in the sea! To swim for a long time, in the deaf, solid water, as if one were returning home to the primordial elements of existence! However, I found these exercises distracted me from my work. They are pleasant for my body, but not good for my soul. And what is not good for my work and my soul is ultimately not good for my body. Therefore I have reduced these pleasures, and in all this, there has been much vanity; to keep young and healthy!... But it is not my business to be young and healthy, nay, not even my business to keep myself free from disease. There is only one thing for a man destined for spiritual work: spiritual work. Perhaps walking is the only kind of exercise we can afford; like prisoners who circle the prison yard for an hour a day. Work is the greatest bondage.</p>"