na veda-yajñādhyayanair na dānair
na ca kriyābhir na tapobhir ugraiḥ
evaṁ-rūpaḥ śakya ahaṁ nṛ-loke
draṣṭuṁ tvad anyena kuru-pravīra
The Bhagavad-gītā gives the description of the universal form. Although this description was unknown to everyone before Arjuna, now one can have some idea of the viśva-rūpa after this incident. Those who are actually divine can see the universal form of the Lord. But one cannot be divine without being a pure devotee of Kṛṣṇa. The devotees, however, who are actually in the divine nature and who have divine vision, are not very much interested in seeing the universal form of the Lord. As described in the previous verse, Arjuna desired to see the four-handed form of Lord Kṛṣṇa as Viṣṇu, and he was actually afraid of the universal form.
In this verse there are some signiﬁcant words, just like veda-yajñādhyayanaiḥ, which refers to studying Vedic literature and the subject matter of sacriﬁcial regulations. Veda refers to all kinds of Vedic literature, such as the four Vedas (Ṛg, Yajur, Sāma and Atharva) and the eighteen Purāṇas, the Upaniṣads and the Vedānta-sūtra. One can study these at home or anywhere else. Similarly, there are sūtras – Kalpa-sūtras and Mīmāṁsā-sūtras – for studying the method of sacriﬁce. Dānaiḥ refers to charity which is offered to a suitable party, such as those who are engaged in the transcendental loving service of the Lord – the brāhmaṇas and the Vaiṣṇavas. Similarly, “pious activities” refers to the agni-hotra and the prescribed duties of the different castes. And the voluntary acceptance of some bodily pains is called tapasya. So one can perform all these – can accept bodily penances, give charity, study the Vedas, etc. – but unless he is a devotee like Arjuna, it is not possible to see that universal form. Those who are impersonalists are also imagining that they are seeing the universal form of the Lord, but from Bhagavad-gītā we understand that the impersonalists are not devotees. Therefore they are unable to see the universal form of the Lord.
There are many persons who create incarnations. They falsely claim an ordinary human to be an incarnation, but this is all foolishness. We should follow the principles of Bhagavad-gītā, otherwise there is no possibility of attaining perfect spiritual knowledge. Although Bhagavad-gītā is considered the preliminary study of the science of God, still it is so perfect that it enables one to distinguish what is what. The followers of a pseudo incarnation may say that they have also seen the transcendental incarnation of God, the universal form, but that is unacceptable because it is clearly stated here that unless one becomes a devotee of Kṛṣṇa one cannot see the universal form of God. So one ﬁrst of all has to become a pure devotee of Kṛṣṇa; then he can claim that he can show the universal form of what he has seen. A devotee of Kṛṣṇa cannot accept false incarnations or followers of false incarnations.
Bhagavad-gītā As It Is 11.48