Śrīmad-Bhāgavatam · Text 3.2.15
Who is speaking and story frame
स्वशान्तरूपेष्वितरै: स्वरूपै-
रभ्यर्द्यमानेष्वनुकम्पितात्मा ।
परावरेशो महदंशयुक्तो
ह्यजोऽपि जातो भगवान् यथाग्नि: ॥ १५ ॥
sva-śānta-rūpeṣv itaraiḥ sva-rūpair
abhyardyamāneṣv anukampitātmā
parāvareśo mahad-aṁśa-yukto
hy ajo ’pi jāto bhagavān yathāgniḥ
The Personality of Godhead, the all-compassionate controller of both the spiritual and material creations, is unborn, but when there is friction between His peaceful devotees and persons who are in the material modes of nature, He takes birth just like fire, accompanied by the mahat-tattva.
Read Śrīla Prabhupāda's purport on Vedabase.io