CC Madhya 19.74

śuciḥ sad-bhakti-dīptāgni-
dagdha-durjāti-kalmaṣaḥ
śva-pāko ’pi budhaiḥ ślāghyo
na veda-jño ’pi nāstikaḥ
Word for word: 
śuciḥ — a brāhmaṇa purified internally and externally; sat-bhakti — of devotional service without motives; dīpta-agni — by the blazing fire; dagdha — burnt to ashes; durjāti — such as birth in a low family; kalmaṣaḥ — whose sinful reactions; śva-pākaḥ api — even though born in a family of dog-eaters; budhaiḥ — by learned scholars; ślāghyaḥ — recognized; na — not; veda-jñaḥ api — even though completely conversant in Vedic knowledge; nāstikaḥ — an atheist.
Translation: 
Śrī Caitanya Mahāprabhu said, “ ‘A person who has the pure characteristics of a brāhmaṇa due to devotional service, which is like a blazing fire burning to ashes all the sinful reactions of past lives, is certainly saved from the consequences of sinful acts, such as taking birth in a lower family. Even though he may be born in a family of dog-eaters, he is recognized by learned scholars. But although a person may be a learned scholar in Vedic knowledge, he is not recognized if he is an atheist.
Purport: 

This verse and the next are quoted from the Hari-bhakti-sudhodaya (3.11, 12), a transcendental literature extracted from the Purāṇas.