When a conditioned soul is awakened to Krsna consciousness and renders service by using his tongue to chant the Lord's holy name & taste the remnants of the Lord's food, the tongue is purified, and one gradually comes to understand who Krsna really is

Expressions researched:
"When a conditioned soul is awakened to Kṛṣṇa consciousness and renders service by using his tongue to chant the Lord’s holy name and taste the remnants of the Lord’s food, the tongue is purified, and one gradually comes to understand who Kṛṣṇa really is"

Sri Caitanya-caritamrta

CC Madhya-lila

“‘Therefore material senses cannot appreciate Kṛṣṇa’s holy name, form, qualities and pastimes. When a conditioned soul is awakened to Kṛṣṇa consciousness and renders service by using his tongue to chant the Lord’s holy name and taste the remnants of the Lord’s food, the tongue is purified, and one gradually comes to understand who Kṛṣṇa really is.’

CC Madhya 17.136, Translation and Purport

“‘Therefore material senses cannot appreciate Kṛṣṇa’s holy name, form, qualities and pastimes. When a conditioned soul is awakened to Kṛṣṇa consciousness and renders service by using his tongue to chant the Lord’s holy name and taste the remnants of the Lord’s food, the tongue is purified, and one gradually comes to understand who Kṛṣṇa really is.’

This verse is recorded in the Bhakti-rasāmṛta-sindhu (1.2.234).