यः शास्त्रविधिमुत्सृज्य वर्तते कामकारतः ।न स सिद्धिमवाप्नोति न सुखं न परां गतिम् ॥
yaḥ śāstravidhimutsṛjya vartate kāmakārataḥ |na sa siddhimavāpnoti na sukhaṃ na parāṃ gatim ||
One who sets aside the injunctions of the scriptures and acts on the impulse of desire does not attain perfection, nor happiness, nor the highest goal.
Explanation
Krishna is closing his teaching on the divine and demonic natures. Having named desire, anger and greed as the three gates to ruin, he says that acting on whim (kāmakāra) instead of the guidance of scripture (śāstra) leads to no success (siddhi), no real happiness and no supreme goal. Traditions differ on what śāstra means here: some stress the Vedic injunctions, others the broader body of ethical and spiritual teaching.