This corresponds to the beginning of Lord Kṛṣṇa’s instructions in Bhagavad-gītā. Tathā dehāntara-prāptiḥ: within this material world, one is simply meant to change from one body to another in different planetary systems. Ūrdhvaṁ gacchanti sattva-sthā: those in the mode of goodness are elevated to the heavenly planets. Adho gacchanti tāmasāḥ: similarly, those too engrossed in ignorance enter the hellish planetary systems. Both of them, however, are subjected to the repetition of birth and death. In Bhagavad-gītā it is stated that even one who is very pious returns to earth after his enjoyment in the higher planetary systems is over (kṣīṇe puṇye martya-lokaṁ viśanti). Therefore, going from one planet to another does not solve the problems of life. The problems of life will only be solved when we no longer have to accept a material body. This can be possible if one simply becomes Kṛṣṇa conscious. As Kṛṣṇa says in Bhagavad-gītā (4.9):
janma karma ca me divyam
evaṁ yo vetti tattvataḥ
tyaktvā dehaṁ punar janma
naiti mām eti so ’rjuna
“One who knows the transcendental nature of My appearance and activities does not, upon leaving the body, take his birth again in this material world, but attains My eternal abode, O Arjuna.” This is the perfection of life and the real solution to life’s problems. We should not be eager to go to the higher, heavenly planetary systems, nor should we act in such a way that we have to go to the hellish planets. The complete purpose of this material world will be fulfilled when we resume our spiritual identities and go back home, back to Godhead. The very simple method for doing this is prescribed by the Supreme Personality of Godhead. Sarva-dharmān parityajya mām ekaṁ śaraṇaṁ vraja. One should be neither pious nor impious. One should be a devotee and surrender to the lotus feet of Kṛṣṇa. This surrendering process is also very easy. Even a child can perform it. Man-manā bhava mad-bhakto mad-yājī māṁ namaskuru. One must always simply think of Kṛṣṇa by chanting Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare. One should become Kṛṣṇa’s devotee, worship Him and offer obeisances to Him. Thus one should engage all the activities of his life in the service of Lord Kṛṣṇa.