Srimad Bhagavatam Canto 03, Chapter 06, Text 06

SB 3.6.6

hiranmayah sa purusah
 sahasra-parivatsaran
anda-kosa uvasapsu
 sarva-sattvopabrmhitah
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
The gigantic virat-purusa, known as Hiranmaya, lived for one thousand celestial years on the water of the universe, and all the living entities lay with Him.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
After the Lord entered each and every universe as the Garbhodakasayi Visnu, half of the universe was filled with water. The cosmic manifestation of the planetary systems, outer space, etc., which are visible to us, is only one half of the complete universe. Before the manifestation takes place and after the entrance of Visnu within the universe, there is a period of one thousand celestial years. All the living entities injected within the womb of the mahat-tattva are divided in all universes with the incarnation of Garbhodakasayi Visnu, and all of them lie down with the Lord until Brahma is born. Brahma is the first living being within the universe, and from him all other demigods and living creatures are born. Manu is the original father of mankind, and therefore, in Sanskrit, mankind is called manusya. Humanity in different bodily qualities is distributed throughout the various planetary systems.
Srimad Bhagavatam Canto 03, Chapter 06, Text 05
Srimad Bhagavatam Canto 03, Chapter 06, Text 07