Sankaracarya's Vivekachudamani 385

विशुद्धमन्तःकरणं स्वरूपे

निवेश्य साक्षिण्यवबोधमात्रे ।

शनैः शनैर्निश्चलतामुपानयन्

पूर्णं स्वमेवानुविलोकयेत्ततः ॥

viśuddhamantaḥkaraṇaṃ svarūpe

niveśya sākṣiṇyavabodhamātre |

śanaiḥ śanairniścalatāmupānayan

pūrṇaṃ svamevānuvilokayettataḥ ||

(Sankaracarya's Vivekachudamani 385)

By fixing the purified inner-organ upon the Self, which is the Witness and Knowledge Absolute and gradually making it quiet, one should behold the state of fullness of one‘s own Self.

The body in which our soul resides is traveling with us in this material world. The body witnessing everything If the body of us doesn't adopt the spiritual knowledge, it will be a waste to be part and parcel of the soul. To make the soul in bliss, the body should be utilized in the understanding of the soul(Atma) and the super soul(Paramatma) If we fail to full fill the joy of the soul, our whole life will be wasted. We will be leaving this body without utilizing the understanding of the soul. We will be missing the chance of understanding about our entire birth.