CC Ādi 5.26

para-vyoma-madhye kari’ svarūpa prakāśa
nārāyaṇa-rūpe karena vividha vilāsa
Word for word: 
para-vyoma-madhye — within the spiritual sky; kari’ — making; svarūpa prakāśa — manifesting His identity; nārāyaṇa-rūpe — the form of Lord Nārāyaṇa; karena — performs; vividha vilāsa — varieties of pastimes.
Translation: 
In the Vaikuṇṭha planets of the spiritual sky the Lord manifests His identity as Nārāyaṇa and performs pastimes in various ways.