Mandukya Karika, verse 3.45
Text
नाऽऽस्वादयेत्सुखं तत्र निःसङ्गः प्रज्ञया भवेत् ।
निश्चलं निश्चरच्चित्तमेकीकुर्यात्प्रयत्नतः ॥ ४५ ॥
nā''svādayetsukhaṃ tatra niḥsaṅgaḥ prajñayā bhavet |
niścalaṃ niścaraccittamekīkuryātprayatnataḥ || 45 ||
45. (The mind) should not be allowed to enjoy the bliss that arises out of the condition of Samādhi. It should be freed from attachment to such happiness through the exercise of discrimination. If the mind, once attaining to the state of steadiness seeks externality, then it should be unified with the Ātman, again, with effort.
Shankara Bhashya (commentary)
The seeker should not taste that happiness that is experienced by the Yogis seeking1 after Samādhi. In other words, he is not to be attached to that happiness. What then should be done by the student? He should be unattached to such happiness, by gaining knowledge through discrimination, and think that whatever happiness is experienced is false2 and conjured up by ignorance. The mind should be turned back from such happiness. When, however, having been once withdrawn from happiness and fixed on the state of steadiness, the mind again manifests its outgoing propensities, then control it by adopting the above-mentioned3 means; and with great care, make it one4 with Ātman; that is, make the mind attain to the condition of pure existence and thought.