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नास्ति बुद्धिरयुक्तस्य न चायुक्तस्य भावना ।
न चाभावयतः शान्तिरशान्तस्य कुतः सुखम् ॥२- ६६॥

naasti buddhirayuktasya na chaayuktasya bhaawanaa ।

na chaabhaawayataH shaantirashaantasya kutaH sukham ॥२- ६६॥

Source: Automatic ITRANS Transliteration

For the non-adherent, there is no wisdom, nor contemplation for the non-adherent.
Nor tranquility for the non-contemplative. What happiness for the non-tranquil?

Source: Milind S. Pandit

There is neither Self-knowledge nor Self-perception to those whose senses are not under control. Without Self-perception there is no peace; and without peace there can be no happiness.

Source: The Bhagavad-Gita: The Sacred Song

One who is not in transcendental consciousness can have neither a controlled mind nor steady intelligence, without which there is no possibility of peace. And how can there be any happiness without peace?

Source: Bhagavad Gita As It Is