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इति गुह्यतमं शास्त्रमिदमुक्तं मयानघ ।
एतद्‌बुद्ध्वा बुद्धिमान्स्यात्कृतकृत्यश्च भारत ॥१५- २०॥

iti guhyatamaM shaastramidamuktaM mayaanagha ।

etad‌buddhwaa buddhimaansyaatkRRitakRRityashcha bhaarata ॥१५- २०॥

Source: Automatic ITRANS Transliteration

Accepting this science so articulated by me, O sinless one,
Having understood this, [one] becomes wise and accomplished in duties, O scion of Bharat.

Source: Milind S. Pandit

Thus this most secret science has been explained by Me, O sinless Arjuna. Having understood this, one becomes enlightened and one's all duties are accomplished.

Source: The Bhagavad-Gita: The Sacred Song

This is the most confidential part of the Vedic scriptures, O sinless one, and it is disclosed now by Me. Whoever understands this will become wise, and his endeavors will know perfection.

Source: Bhagavad Gita As It Is