摩訶止觀 8.91

8.91

又隨諸病處諦心止之，不出三日無有異緣，無不得差。何故爾？如門開則來風，閉扇則靜；心緣外境如開門，止心痛處如閉扇，理數然也。又心如王，病如賊，心安此處，賊則散壞。

Moreover, if one carefully calms the mind wherever the illness is located, without extraneous distractions, within three days there is none that will not heal. Why is this? Just as when the door is opened the wind comes in, but when the leaves are shut it is still; the mind directing attention to external objects is like opening the door, while calming the mind at the painful site is like shutting the leaves; the principle and logic are naturally so. Moreover, the mind is like a king and illness is like a bandit; when the mind is settled in this place, the bandit is dispersed and destroyed.