Srimad Bhagavatam Canto 02, Chapter 05, Text 34

SB 2.5.34

varsa-puga-sahasrante
tad andam udake sayam
kala-karma-svabhava-stho
jivo ’jivam ajivayat
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
Thus all the universes remained thousands of aeons within the water [the Causal Ocean], and the Lord of living beings, entering in each of them, caused them to be fully animated.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
The Lord is described here as the jiva because He is the leader of all other jivas (living entities). In the Vedas He is described as the nitya, the leader of all other nityas. The Lord’s relation with the living entities is like that of the father with the sons. The sons and the father are qualitatively equal, but the father is never the son, nor is the son ever the father who begets. So, as described above, the Lord as Garbhodakasayi Visnu or Hiranyagarbha Supersoul enters into each and every universe and causes it to be animated by begetting the living entities within the womb of the material nature, as confirmed in the Bhagavad-gita (14.3). After each annihilation of the material creation, all the living entities are merged within the body of the Lord, and after creation they are again impregnated within the material energy. In material existence, therefore, the material energy is seemingly the mother of the living entities, and the Lord is the father. When, however, the animation takes place, the living entities revive their own natural activities under the spell of time and energy, and thus the varieties of living beings are manifested. The Lord, therefore, is ultimately the cause of all animation in the material world.
 
Srimad Bhagavatam Canto 02, Chapter 05, Text 33
Srimad Bhagavatam Canto 02, Chapter 05, Text 35