So when creation has taken place, the things should be managed properly, so Kṛṣṇa Himself, He expands into three forms for management. One form is Lord Viṣṇu, one form is Lord Śiva and the other form is Lord Brahmā. Brahmā creates, Lord Viṣṇu maintains, and Lord Śiva destroys. Because in the material nature, you cannot have anything permanent. That is material nature. It is just like the flashlight. When you pass through roads and avenue, there are three colors-red, blue and yellow. They're passing through, always. Not that the blue is always existing, or red is always existing, or the yellow is always. Passing, simply. That is the nature, material nature. Here, everything is born. That is called sṛṣṭi, creation.
Everything is creation. That is our experience. Everything is created and it is maintained for some time. Just like my body, your body, is created. And it will be maintained for sometimes. But at the end, when the body is old, it will be destroyed. This is material nature. Some of the philosophers, they say there is no such thing, creation or destruction; everything is existing always. That we also accept. That everything is existing always means Kṛṣṇa. And Kṛṣṇa... The creation is going through three stages. The creation taking place, it is being maintained for some time, and again it is destroyed. These things are going on. The same example: the lights, flashlights. They are coming and going. But the puller of the lights, behind the light, he is existing. Similarly, the creator is existing, but not the creation. Creation is coming into existence, is sustained, and again... But the creator is there. Aham evāsam agre. Lord Kṛṣṇa says that "Before creation I was there." Otherwise who will create? "Before creation I was there. While creation is maintained, I am there. And when it is destroyed, still I am there."
Prabhupada's lecture - Śrīmad-Bhāgavatam 1.2.23 - Los Angeles, August 26, 1972