We pray for many things from God—health, wealth, respect, love, a house, a vehicle, marriage. There is nothing wrong with this. But after achieving an audience with Yamaraja, should Nachiketas be asking for the same things? The highest plane is that of the Devas, the Swarga. Below that is antariksha, which is the plane of celestial beings like Yakshas and Gandharvas. Down below is earth. Health, wealth, and all are transient, silly issues of the earthly plane. You would remember, when Nachiketas wanted to know what happens after death, Yamaraja said, 'I can give you wealth, longevity as long as you want, or enjoyment with apsaras in lieu of this question.' Nachiketas said, 'You cannot satisfy anyone with money. Give him 10, he will want to have 100. Give him 100, he will look to get 1000. Give him 1000, he will ask for 10000.' It's the same case with longevity also. Nachiketas says, after having attained the audience of Yamaraja, he would be a fool to ask for such silly things. He should rather ask for immortality. Remember this, when you become close to Bhagavan. Remember this. It won't be wise to ask for the same things. If you are a true devotee, it is guaranteed that Bhagavan is already taking care of all your needs. An infant doesn't have to ask its mother for food or other needs. When you are face to face with Bhagavan, you should be asking for knowledge, the eternal knowledge that will make you immortal. Realizing Atma-tattva is what makes you immortal because then you have no more rebirths. This is what Nachiketas says in the 28th mantra of the Prathama Valli of Kathopanishad.

अजीर्यताममृतानामुपेत्य
जीर्यन्मर्त्यः क्वधःस्थः प्रजानन् ।
अभिध्यायन् वर्णरतिप्रमोदान्
अतिदीर्घे जीविते को रमेत ॥

But Nachiketas also points out that at the surface level, all these comforts look enjoyable, pleasure-giving. Only when you contemplate—अभिध्यायन्—their futility becomes evident.

So he says -

यस्मिन्निदं विचिकित्सन्ति मृत्यो
यत्साम्पराये महति ब्रूहि नस्तत् ।
योऽयं वरो गूढमनुप्रविष्टो
नान्यं तस्मान्नचिकेता वृणीते ॥

He doesn't want to waste the boons that Yamaraja gives him. He says, 'I am clear what I want. You can't distract me with these silly things. Tell me what happens after death.' Thus ends the Prathama Valli of Prathamadhyaya of Kathopanishad.