Katha-2-3-19-saha nāvavatu

Sri Shankara’s Commentary (Bhashya) translated by S. Sitarama Sastri

This sânti (expiatory prayer) is stated here for the purpose of removing all faults incurred by the disciple and preceptor, in the course of receiving, and imparting knowledge respectively, and caused by dereliction of rules due to oversight or excitement. Let him protect us both by illumining the nature of knowledge. Who? He alone, the Lord of all, revealed by the Upanishads. Again, let him protect us both, by revealing the fruits of such knowledge. Let us together acquire the strength produced by knowledge. Moreover, may what is studied by us, who are bright, be well studied! Or may what is studied, i.e., acquired by study, by us, be very potent! May we, disciple and preceptor, never hate each other, owing to blame incurred by us, by improper recital or instruction due to oversight! The repetition three times of ‘Peace,’ as ‘Peace! Peace! Peace!’ is for averting all evil. The word Om is to show that the Upanishad ends here.

॥ इति काठकोपनिषदि द्वितीयाध्याये तृतीया वल्ली ॥

|| iti kāṭhakopaniṣadi dvitīyādhyāye tṛtīyā vallī ||

Here ends the Kathopanishad.

Links
Various resources on the Kathopanishad
Upanishad Series – Katopanishad Commentary by Swami Chinmayananda