जानाम्यहं शेवधिरित्यनित्यं न ह्यध्रुवैः प्राप्यते हि ध्रुवं तत् । ततो मया नाचिकेतश्चितोऽग्निः अनित्यैर्द्रव्यैः प्राप्तवानस्मि नित्यम् ॥ १०॥

ॐ

English Translation

Yama said: I know that the treasure resulting from action is not eternal; for what is eternal cannot be obtained by the non- eternal. Yet I have performed the Nachiketa sacrifice with the help of non-eternal things and attained this position which is only relatively eternal. 

ॐ

English Commentary

Delighted, Death says again: I know that the treasure, i.e., the reward of Karma, because it is sought after like a treasure, is not eternal; for, that which is constant, i.e., the treasure named Paramâtman cannot be reached by things not constant. That treasure alone, which is in the nature of uncertain happiness, can be obtained by uncertain things. Therefore, by me, though I know that the eternal cannot be attained by ephemeral aids, has been propitiated, the fire Nachikêtas leading to the attainment of heavenly joys with ephemeral things. By virtue of that, I have attained the position of authority, this office of Death known as Svarga eternal, but only relatively.

shri Shankaracharya