Bhagavad Gita · 14.1

श्रीभगवानुवाचपरं भूयः प्रवक्ष्यामि ज्ञानानां ज्ञानमुत्तमम्।यज्ज्ञात्वा मुनयः सर्वे परां सिद्धिमितो गताः॥

śhrī bhagavān uvācha paraṁ bhūyaḥ pravakṣhyāmi jñānānāṁ jñānam uttamam yaj jñātvā munayaḥ sarve parāṁ siddhim ito gatāḥ

The Supreme Lord said: I shall once again declare to you the supreme knowledge, the best of all knowledge, knowing which all the sages have attained the highest perfection.

— Bhagavad Gita 14.1

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)