Sanskrit
तस्माच्छास्त्रं प्रमाणं ते कार्याकार्यव्यवस्थितौ । ज्ञात्वा शास्त्रविधानोक्तं कर्म कर्तुमिहार्हसि ॥
tasmāc chāstraṃ pramāṇaṃ te kāryākāryavyavasthitau jñātvā śāstravidhānoktaṃ karma kartum ihārhasi
Translation
Therefore let the Scriptures be thy authority, in determining what ought to be done, or what ought not to be done. Knowing what hath been declared by the ordinances of the Scriptures, thou oughtest to work in this world.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
The chapter closes on a firmly textualist note: let scripture be the authority (pramāṇam) for determining what should and shouldn’t be done, and act according to what it prescribes. This is a conservative resting point for a text that elsewhere leans toward internalized discernment — the steady wisdom praised in Chapter 2, the situational duty of svadharma in Chapter 3, even Krishna’s own final concession in Chapter 18 to let Arjuna decide as he wishes. Chapter 17 opens by probing exactly that tension, asking whether sincerity and scriptural correctness are really the same axis or two different ones — a question this closing verse doesn’t anticipate needing to answer.