This is a lecture from the book Caitanya-caritāmṛta, Madhya-līlā 20.98-99 that Srila Prabhupada gave on July 4, 1974 in Washington, D.C..
There is a supreme controller, as in every department, in every state, every affair, every business, every institution there is a controller. That you have got experience, practical. Without controller, nothing can be properly discharged. Controller is required.
So the śāstra says that controller or ruler is the same, and the Sanskrit synonym is īśvara. Īśvara means controller or ruler. So there are different kinds of controllers according to time, sphere. Just like in your country, the President is the controller. In other country somebody is controller. So there are many hundreds and thousands of planets within this universe, and each and every planet there is a controller. The sun planet, there is a controller. His name is Vivasvān. That we find. Similarly, the moon planet, there is a controller. Every planet, there is controller. And above all of them there is another supreme controller of the universe, the Brahma, and there are many millions of brahmāṇḍas, or universes. So there are controllers. But so far Kṛṣṇa is concerned, He is described in the śāstras, Brahma-saṁhitā, īśvaraḥ paramaḥ kṛṣṇaḥ [Bs. 5.1].
There are controllers, but the supreme controller is Kṛṣṇa. Īśvaraḥ paramaḥ kṛṣṇaḥ. Īśvaraḥ means controller. Sac-cid-ānanda-vigrahaḥ [Bs. 5.1]. His form... He has form. Bhagavān means with form. You see the form here, vigrahaḥ. Vigrahaḥ means form. But His form is different from our. He's sac-cid-ānanda. His form is eternal. Our, this form is not eternal. We have to give it up. We have to accept another form according to our karma. Tathā dehāntara-prāptiḥ [Bg. 2.13]. But Kṛṣṇa hasn't got to do that. He is in His original form. He has got many forms, expansions, but His original form is Kṛṣṇa with two hands and flutes.