摩訶止觀 4.151

4.151

睡眠蓋者，心神昏昏為「睡」；六識闇塞、四支倚放為「眠」。眠名「增心數法」，烏闇沈塞，密來覆人，難可防衛。五情無識猶如死人，但於片息名為「小死」。若喜眠者，眠則滋多，《薩遮經》云：「若人多睡眠，懈怠妨有得；未得者不得，已得者退失。若欲得勝道，除睡、疑、放逸，精進策諸念，離惡功德集。」《釋論》云：「眠為大闇無所見，日日欺誑奪人明；亦如臨陣白刃間，如共毒蛇同室居。如人被縛將去殺，爾時云何安可眠？」眠之妨禪，其過最重。是為睡眠蓋相。

As for the hindrance of drowsiness and sleep: the mental spirit becoming dull and dazed is 'drowsiness'; the six consciousnesses becoming dark and blocked and the four limbs resting limp is 'sleep'. Sleep is called an 'aggravating mental factor'; pitch-black and sunkenly blocking, it secretly comes and covers a person, hard to defend against. The five senses devoid of consciousness are like a dead corpse; merely having a tiny breath, it is called 'a minor death'. If one delights in sleep, sleep will multiply. The Satyaka Sūtra states: 'If a person sleeps much, / Laziness hinders attainment; / What is not yet attained will not be attained, / And what has already been attained will be lost. / If one wishes to attain the supreme path, / Eliminate sleep, doubt, and heedlessness, / Diligently urge all thoughts forward, / And depart from evil to gather merit.' The Mahāprajñāpāramitopadeśa states: 'Sleep is a great darkness with nothing to be seen; / Day after day it deceives and robs people of their light. / It is also like confronting the battlefield amid naked blades, / Or dwelling in the same room with a venomous snake. / Like a person bound and about to be led away for execution, / At such a time, how could one comfortably sleep?' Sleep's hindrance to dhyāna is of the gravest fault. This is the characteristic of the hindrance of drowsiness and sleep.