Sanskrit
पुरुषः प्रकृतिस्थो हि भुङ्क्ते प्रकृतिजान्गुणान् । कारणं गुणसङ्गोऽस्य सदसद्योनिजन्मसु ॥
puruṣaḥ prakṛtistho hi bhuṅkte prakṛtijān guṇān kāraṇaṃ guṇasaṅgo 'sya sadasadyonijanmasu
Translation
Spirit seated in Matter useth the qualities born of Matter; attachment to the qualities is the cause of his births in good and evil wombs.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
This verse supplies the mechanism verse 21 left implicit: purusha, “seated in” prakriti, uses the qualities (gunas) that prakriti produces, and it’s specifically attachment (sanga) to those qualities — not mere contact with them — that causes rebirth into good or evil wombs. The distinction matters practically: contact with the gunas is unavoidable for anything embodied, but the text locates the actual cause of bondage in the attachment layered on top of that contact, which is a problem of orientation rather than of embodiment itself.