Sanskrit
तमस्त्वज्ञानजं विद्धि मोहनं सर्वदेहिनाम् । प्रमादालस्यनिद्राभिस्तन्निबध्नाति भारत ॥
tamas tv ajñānajaṃ viddhi mohanaṃ sarvadehinām pramādālasyanidrābhis tan nibadhnāti bhārata
Translation
But Inertia, know thou, born of unwisdom, is the deluder of all dwellers in the body; that bindeth by heedlessness, indolence and sloth, O Bhârata.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
Tamas defined, completing the triad begun at verse 6: born of unwisdom itself, it deludes and binds through negligence, indolence, and sleep. With all three now defined, the shape of the argument is visible — sattva binds through refined attachment, rajas through craving-driven action, tamas through sheer inertia — three qualitatively different chains, not a simple better-worse-worst ranking, even though verse 18 will later map them onto upward, middle, and downward destinies.