Kāraṇam The reason is that the dehī within the body, the soul, he is associating with different types of the modes of material nature. Kāraṇaṁ guṇa-saṅgaḥ asya sad-asad-janma-yoniṣu. Therefore he is getting different types of body. It is naturally going on. You haven't got to aspire for your next body, different . . . but it must be different body. Tathā dehāntara-prāptiḥ (BG 2.13). You have to change this body, but Kṛṣṇa does not say what kind of body. That will depend on your qualification. Kāraṇaṁ guṇa-saṅgaḥ asya. Qualification. If you associate with sattva-guṇa, then ūrdhvaṁ gacchanti sattva-sthāḥ (BG 14.18), then you are elevated to the higher planetary system. Madhye tiṣṭhanti rājasāḥ. If you are associating with the modes of passion, then you will remain here. And jaghanya-guṇa-vṛtti-sthā adho gacchanti tāmasāḥ: and if you associate with the tamo-guṇa, then you go lower and lower, abominable family, lower family, animal family, or trees, plants, like that.
So the 8 . . . 8,400,000 forms of life is due to kāraṇaṁ guṇa-saṅgaḥ asya. And according to the body, there are distresses and happinesses. You cannot expect in the dog's body the same happiness as a king or a very rich man is enjoying. Kāraṇaṁ guṇa-sa . . . he has got the dog's body, he has got the king's body. Kāraṇaṁ guṇa-saṅgo 'sya (BG 13.22). So this happiness or that happiness, this distress or that distress, they are all due to this material body. Therefore yoga means one has to transcend this happiness of body, distress or happiness. That is here said, that atyanta-uparatiḥ yatra. If you connect yourself again with the supreme yoga—that is called real yoga—then you get rid of this so-called material happiness and distress, which is due to this body.
So that is wanted. That is ādhyātmika. That is called bhakti-yoga, to reconnect our connection with Kṛṣṇa. Kṛṣṇa also comes to instruct that, "You rascal, sarva-dharmān parityajya mām ekaṁ śaraṇaṁ vraja (BG 18.66). Just revive your connection with Me, you rascal. Give up all these manufactured so-called types of yoga and religion." Sarva-dharmān paritya . . . That is Kṛṣṇa's instruction. That is the differ . . . that is the proof. Kṛṣṇa says the same thing, and Kṛṣṇa's representative or incarnation or guru says the same thing. That is the qualification of guru. Here Kapiladeva, although He is the incarnation of Kṛṣṇa, He's acting as the representative of Kṛṣṇa as guru. He's saying the same thing. He does not say another thing. Yoga ādhyātmikaḥ. Yoga ādhyātmikaḥ puṁsāṁ mato niḥśreyasāya me. Niḥśreyasa means the ultimate benefit. Kṛṣṇa also says the same thing, that paraṁ guhyatamam: "I have instructed you so many things, but because you are My dear friend, I am just disclosing to you the most confidential thing." What is that? Sarva-dharmān parityajya mām ekaṁ śaraṇaṁ vraja. If you accept this principle, then you become actually transcendental to this so-called material happiness and distress. That is yoga.