CC Madhya 6.171
jagad-rūpa haya īśvara, tabu avikāra
“The touchstone, after touching iron, produces volumes of gold without being changed. Similarly, the Supreme Personality of Godhead manifests Himself as the cosmic manifestation by His inconceivable potency, yet He remains unchanged in His eternal, transcendental form.
According to the commentary of Śrīla Bhaktisiddhānta Sarasvatī Ṭhākura, the purpose of the janmādy asya verse in the Vedānta-sūtra is to establish that the cosmic manifestation is the result of the transformation of the potencies of the Supreme Personality of Godhead. The Supreme Lord is the master of innumerable eternal energies, which are unlimited. Sometimes these energies are manifested, and sometimes they are not. In any case, all energies are under His control; therefore He is the original energetic, the abode of all energies. A common brain in the conditioned state cannot conceive of how these inconceivable energies abide in the Supreme Personality of Godhead, how He exists in His innumerable forms as the master of both spiritual and material energies, how He is the master of both manifest and potential powers, and how contradictory potencies can abide in Him. As long as the living entity is within this material world, in the condition of illusion, he cannot understand the activities of the inconceivable energies of the Lord. Thus the Lord’s energies, though factual, are simply beyond the power of the common brain to understand.
When the atheistic philosophers or the Māyāvādīs, being unable to understand the inconceivable energies of the Supreme Personality of Godhead, imagine an impersonal void, their imagination is only the counterpart of materialistic thinking. Within the material world, there is nothing inconceivable. High-thinking philosophers and scientists can tackle the material energy, but not being able to understand the spiritual energy, they can simply imagine an inactive state, such as the impersonal Brahman. This is simply the negative side of material life. By such imperfect knowledge, the Māyāvādī philosophers conclude that the cosmic manifestation is a transformation of the Supreme. Thus they must necessarily also accept the theory of the illusion of the Supreme (vivarta-vāda). However, if we accept the inconceivable potencies of the Lord, we can understand how the Supreme Personality of Godhead can appear within this material world without being touched or contaminated by the three modes of material nature.
From the śāstras we learn that there is a stone or jewel called a touchstone that can transform iron into gold. Although the touchstone turns iron into gold many times, it remains in its original condition. If such a material stone can maintain its inconceivable energy after producing volumes of gold, certainly the Supreme Personality of Godhead can remain in His original sac-cid-ānanda form after creating the cosmic world. As confirmed in the Bhagavad-gītā (9.10), He acts only through His different energies. Mayādhyakṣeṇa prakṛtiḥ: Kṛṣṇa directs the material energy, and that potency works in this material world. This is also confirmed in the Brahma-saṁhitā (5.44):
chāyeva yasya bhuvanāni bibharti durgā
icchānurūpam api yasya ca ceṣṭate sā
govindam ādi-puruṣaṁ tam ahaṁ bhajāmi
The durgā-śakti (material energy) acts under the direction of the Supreme Personality of Godhead, and the universal creation, maintenance and destruction are being carried out by the durgā-śakti. Kṛṣṇa’s direction is in the background. The conclusion is that the Supreme Personality of Godhead remains as He is, even though directing His energy, which makes the diverse cosmic manifestation work so wonderfully.