9:2
राजविद्या राजगुह्यं पवित्रमिदमुत्तमम् ।
प्रत्यक्षावगमं धर्म्यं सुसुखं कर्तुमव्ययम् ॥९- २॥
raajawidyaa raajaguhyaM pawitramidamuttamam ।
pratyakShaawagamaM dharmyaM susukhaM kartumawyayam ॥९- २॥
Source: Automatic ITRANS Transliteration
This most holy knowledge-king, secret-king,
Proximately understood virtue, joyfully performed, [is] imperishable.
Source: Milind S. Pandit
This knowledge is the king of all knowledge, is the most secret, is very sacred, it can be perceived by instinct, conforms to Dharma, is very easy to practice, and is imperishable.
This knowledge is the king of education, the most secret of all secrets. It is the purest knowledge, and because it gives direct perception of the self by realization, it is the perfection of religion. It is everlasting, and it is joyfully performed.
Source: Bhagavad Gita As It Is