CC Madhya 22.98
jighāṁsayāpāyayad apy asādhvī
lebhe gatiṁ dhātry-ucitāṁ tato ’nyaṁ
kaṁ vā dayāluṁ śaraṇaṁ vrajema
aho — how wonderful; bakī — Pūtanā, the sister of Bakāsura; yam — whom; stana — on the two breasts; kāla-kūṭam — the deadly poison; jighāṁsayā — with a desire to kill; apāyayat — forced to drink; api — although; asādhvī — dangerously inimical to Kṛṣṇa; lebhe — achieved; gatim — the destination; dhātrī — for a nurse; ucitām — suitable; tataḥ — than Him; anyam — other; kam — to whom; vā — or; dayālum — the most merciful; śaraṇam — shelter; vrajema — shall take.
“ ‘Oh, how wonderful it is! Pūtanā, the sister of Bakāsura, wanted to kill Kṛṣṇa by smearing deadly poison on her breasts and having Kṛṣṇa take it. Nonetheless, Lord Kṛṣṇa accepted her as His mother, and thus she attained the destination befitting Kṛṣṇa’s mother. Of whom should I take shelter but Kṛṣṇa, who is most merciful?’
This is a quotation from Śrīmad-Bhāgavatam (3.2.23).