Katha-1-1-12-svarge loke

12-13  Nachiketa said: In the Heavenly World there is no fear whatsoever. You, O Death, are not there and no one is afraid of old age. Leaving behind both hunger and thirst and out of the reach of sorrow, all rejoice in Heaven. You know, O Death, the Fire-sacrifice, which leads to Heaven. Explain it to me, for I am full of faith. The inhabitants of Heaven attain immortality. This I ask as my second boon.