Katha-1-1-16-tamabravīt

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

How? He said to Nachikêtas, being delighted with, i.e., experiencing great delight at the sight of true discipleship, and being liberal-minded ‘I give you now here this other boon, the fourth, being pleased with you; the fire that I have explained shall become celebrated by your name alone. Moreover, accept this sounding garland set with precious stones and wonderful’; or, the word ‘srinkâm’ may mean ‘the no mean goal that can be attained by karma the whole passage signifying ‘ accept also the knowledge of Karma because it is the source of many fruits.

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