摩訶止觀 9.21

9.21

兩心前、後、中間，必有持身法。此法起時，自然身體正直，不疲不痛，如似有物扶助身力。若惡持，來時緊急勁痛，去時寬緩疲困，此是麁惡持法。若好持法，持麁細住，無寬急過。或一兩時，或一兩日，或一兩月，稍覺深細，豁爾心地作一分開明，身如雲如影，煚然明淨，與定法相應，持心不動，懷抱淨除，爽爽清冷。隨復空淨，而猶見身、心之相，未有支林功德，是名「欲界定」。

Before, after, and in between these two states of mind, there must be a dharma that sustains the body. When this dharma arises, the body naturally becomes straight and upright, without fatigue or pain, as if something were assisting the body's strength. If it is an unwholesome sustaining, it arrives urgently with acute pain and departs with looseness and exhausted weariness; this is a coarse and unwholesome sustaining dharma. If it is a wholesome sustaining dharma, it sustains coarse and subtle abiding without the faults of looseness or urgency. After one or two hours, or one or two days, or one or two months, one gradually perceives it to become deep and subtle; suddenly, a fraction of opening illumination occurs in the ground of the mind, the body becomes like a cloud or a shadow, brightly pure, corresponding with the concentration dharma; sustaining the mind without movement, the chest is purified and relieved, refreshingly cool and clear. Thereupon it becomes empty and pure, yet one still perceives the marks of body and mind, and does not yet possess the virtues of the branches and factors; this is called 'desire-realm concentration.'