Svarüpa of the Ätmä
Lord Yama then describes the svarüpa of the Ätmä,
Tr. – That is not comprehensible by sound, touch, is form-less, un-decaying, tasteless, not subject to time, odourless, beginning less and without end. It is distinct from Mahat and is ever constant. Knowing this one becomes free from the jaws of death. (I.3.15)
-Katha Upanishad, Chapter 1, Verse 3.15