When lying down the breath is least strained, by sitting it is more strained, by standing still more, and by walking and running still more again. The influence of passions quickens it most; for this reason the life of celibacy has been practiced by ancient mystics, and that is why the Sufi finds it necessary at times to lead a secluded life, which settles his external self as well as his mind. This does not only help to create peace and harmony in man, but even to prolong life much longer than the allotted time.