CC Madhya 24.339

sādhu-lakṣaṇa, sādhu-saṅga, sādhu-sevana
asat-saṅga-tyāga, śrī-bhāgavata-śravaṇa
Word for word: 
sādhu-lakṣaṇa — the symptoms of a devotee; sādhu-saṅga — association with devotees; sādhu-sevana — offering service to devotees; asat-saṅga-tyāga — giving up the company of nondevotees; śrī-bhāgavata-śravaṇa — regularly hearing the recitation of Śrīmad-Bhāgavatam.
Translation: 
“You should describe the symptoms of a devotee, how to associate with devotees, how to satisfy a devotee by rendering service, and how to give up the association of nondevotees. You should also explain the value of regularly hearing the recitation of Śrīmad-Bhāgavatam.