CC Ādi 5.80

sei puruṣa sṛṣṭi-sthiti-pralayera kartā
nānā avatāra kare, jagatera bhartā
Word for word: 
sei — that; puruṣa — the Personality of Godhead; sṛṣṭi-sthiti-pralayera — of creation, maintenance and annihilation; kartā — creator; nānā — various; avatāra — incarnations; kare — makes; jagatera — of the material world; bhartā — maintainer.
Translation: 
That puruṣa [Kāraṇodakaśāyī Viṣṇu] is the performer of creation, maintenance and destruction. He manifests Himself in many incarnations, for He is the maintainer of the world.