CC Madhya 25.132
tattvaṁ yaj jñānam advayam
bhagavān iti śabdyate
vadanti — they say; tat — that; tattva-vidaḥ — those who know the Absolute Truth; tattvam — the ultimate goal; yat — which; jñānam advayam — identical knowledge; brahma iti — as the impersonal Brahman; paramātmā iti — as the Supersoul; bhagavān iti — as the Supreme Personality of Godhead; śabdyate — it is described.
“ ‘The Absolute Truth is known by the self-realized souls as a unified identity known by different names — impersonal Brahman, localized Paramātmā, and Bhagavān, the Supreme Personality of Godhead.’
This is a quotation from Śrīmad-Bhāgavatam (1.2.11). For an explanation see Ādi-līlā, chapter two, text 11.