Sanskrit
रजो रागात्मकं विद्धि तृष्णासङ्गसमुद्भवम् । तन्निबध्नाति कौन्तेय कर्मसङ्गेन देहिनम् ॥
rajo rāgātmakaṃ viddhi tṛṣṇāsaṅgasamudbhavam tan nibadhnāti kaunteya karmasaṅgena dehinam
Translation
Motion, the passion nature, know thou, is the source of attachment and thirst for life, O Kaunteya, that bindeth the dweller in the body by the attachment to action.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
Rajas defined: passion-natured, the source of craving (trishna) and attachment, binding through compulsive attachment to action. This is essentially the engine behind the causal chain chapter 2 laid out at 2.62-63 — dwelling on objects to attachment to desire to anger to ruin — named here as a guna rather than traced step by step. Where sattva’s leash was happiness and knowledge, rajas’s is restless doing itself, action pursued not for its own sake but because craving keeps generating more of it.