Śrī Caitanya Caritamrta · Text Madhya 6.103
কৃষ্ণবর্ণং ত্বিষাঽকৃষ্ণং সাঙ্গোপাঙ্গাস্ত্রপার্ষদম্ ।
যজ্ঞৈঃ সংকীর্তনপ্রায়ৈর্যজন্তি হি সুমেধসঃ ॥ ১০৩ ॥
kṛṣṇa-varṇaṁ tviṣākṛṣṇaṁ
sāṅgopāṅgāstra-pārṣadam
yajñaiḥ saṅkīrtana-prāyair
yajanti hi su-medhasaḥ
“ ‘In this Age of Kali, those who are intelligent perform the congregational chanting of the Hare Kṛṣṇa mahā-mantra, worshiping the Supreme Personality of Godhead, who appears in this age always describing the glories of Kṛṣṇa. That incarnation is yellowish in hue and is always associated with His plenary expansions [such as Śrī Nityānanda Prabhu] and personal expansions [such as Gadādhara], as well as His devotees and associates [such as Svarūpa Dāmodara].’
Read Śrīla Prabhupāda's purport on Vedabase.io