Kṛṣṇa says in the Bhagavad-gītā, ābrahma-bhuvanāl lokāḥ punar āvartino 'rjuna (BG 8.16). Even if you, by activities, pious activities, or worshiping different demigods, you go to the Brahmaloka, where the standard of life is very, very great, life is also, duration of life is very, very great, so that is not permanent. But our problem is that we are permanent, eternal, and we are trying to be happy in the nonpermanent condition of life. This is called less brain. My problem is that I am the spirit soul... Nityaḥ śāśvataḥ. I am eternal, śāśvataḥ. Na hanyate hanyamāne śarīre (BG 2.20). I do not die even after the annihilation of this body. Then where is my eternal body? This question should be raised by the human form of life. Athāto brahma jijñāsā.
But instead of athāto... Jīvasya tattva-jijñāsā. Jīvasya, the only business is "How, what is the aim of life, how I shall be eternally happy, how I shall get my eternal life." That is the problem. But they do not consider the real problem. They think, "Immediately I require some money. So let me worship Lord Śiva or Lord..., this, Goddess Durgā, or Gaṇeśa, or Sūrya..." There are so many, recommended. So that is condemned in the Bhagavad-gītā that tad bhavaty alpa, antavat tu phalaṁ teṣāṁ tad bhavaty alpa-medhasām (BG 7.23).
But people are... They do not care. Of course, those who are worshiping demigods, apart from them, there are many atheists. They don't care for anything. They want simply sense enjoyment. But it is said that you can get some immediate profit by worshiping different demigods. That is all right. But that is not your permanent benefit. Because karmaṇā, you are creating... Karmaṇāṁ siddhim. You are getting some profit by your karma, fruitive karma, but you are creating another life, another life. To enjoy the fruitive result of this karma you'll have to wait for next life. So next life means another material body. So another material body means another term of suffering, another chapter of suffering. That they do not understand.
Therefore Ṛṣabhadeva advising that "This is not good. Don't be engaged in karma, fruitive activities." If you be engaged in fruitive activities, karma, then you'll have to accept another material body. That may be a cat's body or dog's body or demigod's body or... Body you'll have to... But as soon as you have a material body, then you'll suffer. The... One who does not understand this philosophy, he's called alpa-medhasa, poor fund of knowledge. Poor fund of knowledge.
Real problem is, as Kṛṣṇa says, janma-mṛtyu-jarā-vyādhi-duḥkha-doṣānudarśanam (BG 13.9), that I am implicated with this process of repetition of birth and death, and after birth, there is suffering, old age, disease. He does not consider it. He thinks, "This is natural." No, it is unnatural. One who does not understand this, he's alpa-medhasa, poor, poor fund of knowledge.