Naturally (SB cantos 1 - 3)
Srimad-Bhagavatam
SB Canto 1
SB 1.1.1, Purport:
It is natural that a philosophical mind wants to know about the origin of the creation. At night he sees the stars in the sky, and he naturally speculates about their inhabitants. Such inquiries are natural for man because man has a developed consciousness which is higher than that of the animals. The author of Śrīmad-Bhāgavatam gives a direct answer to such inquiries. He says that the Lord Śrī Kṛṣṇa is the origin of all creations. He is not only the creator of the universe, but the destroyer as well. The manifested cosmic nature is created at a certain period by the will of the Lord. It is maintained for some time, and then it is annihilated by His will.