Shloka 15
Adhyāya 240: Indriya–Manas–Buddhi–Ātman — The Inner Hierarchy and Restraint (इन्द्रिय-मनस्-बुद्धि-आत्म-क्रमः)
योगी मन और इन्द्रियोंको एकाग्र करके रातके पहले और पिछले पहरमें ध्यानस्थ होकर मनको आत्मामें लगावे ।।
jantoh pañcendriyasya asya yad ekaṁ chidram indriyam | tato 'sya sravate prajñā dhṛteḥ pādād ivodakam | sattva-saṁsevanād dhīro nidrām ucchettum arhati ||
毗耶娑说：凡具五根之有情，若其中一根成为“漏处”——破口外驰，趋向其境——则其智慧便从此流失，如水自器皿之孔而泄。是故，坚忍之人当修习萨埵（sattva，清明与平衡），由此方堪断除睡眠与昏钝。在瑜伽的戒律中，应将所认定的过失——欲、嗔、贪、惧与睡——尽皆拔除：以内在的制御胜嗔，以舍弃强迫性的决断胜欲，并以持续培育萨埵克服懈怠沉滞。
व्यास उवाच
Educational Q&A
Even a single unguarded sense can drain discernment and steadiness; therefore one should practice disciplined restraint and cultivate sattva to uproot torpor and the major yogic faults (desire, anger, greed, fear, and sleep).
In the Śānti Parva’s instruction on inner discipline, Vyāsa teaches by analogy: like water escaping through a small hole, wisdom escapes when any one sense turns outward unchecked; he then prescribes sattvic cultivation and specific methods of conquering inner enemies.