Katha Upanishad - Verse 1.3.15
Text: अशब्दमस्पर्शमरूपमव्ययं तथाऽरसन्नित्यमगन्धवच्च यत् । अनाद्यनन्तं महतः परं ध्रुवं निचाय्य तन्मृत्युमुखात्प्रमुच्यते ॥ १५ ॥ aśabdamasparśamarūpamavyayaṃ tathā’rasannityamagandhavacca yat | anādyanantaṃ mahataḥ paraṃ dhruvaṃ nicāyya tanmṛtyumukhātpramucyate || 15 || 15. Which is soundless, touchless, formless, undecaying, so tasteless, eternal and scentless, beginningless, endless, beyond the Mahat, and constant, knowing that, man escapes from the mouth of Death. Shankara’s Commentary: How the object to be known is very subtle is explained. This earth produced by sound, touch, form, taste and scent, and the object of all the senses, is gross; so is the body....