SB 12.6.12

taṁ tarpayitvā draviṇair
 nivartya viṣa-hāriṇam
dvija-rūpa-praticchannaḥ
 kāma-rūpo ’daśan nṛpam
Synonyms: 
tam — him (Kaśyapa); tarpayitvā — gratifying; draviṇaiḥ — with valuable offerings; nivartya — stopping; viṣa-hāriṇam — an expert in counteracting poison; dvija-rūpa — in the form of a brāhmaṇa; praticchannaḥ — disguising himself; kāma-rūpaḥ — Takṣaka, who could assume any form he wished; adaśat — bit; nṛpam — King Parīkṣit.
Translation: 
Takṣaka flattered Kaśyapa by presenting him with valuable offerings and thereby stopped the sage, who was expert in counteracting poison, from protecting Mahārāja Parīkṣit. Then the snake-bird, who could assume any form he wished, disguised himself as a brāhmaṇa, approached the King and bit him.
Purport: 

Kaśyapa could counteract the poison of Takṣaka and demonstrated this power by bringing a palm tree back to life after Takṣaka had burned it to ashes by biting it with his fangs. According to the arrangement of destiny, Kaśyapa was diverted by Takṣaka, and the inevitable took place.