CC Antya 2.14

sei jīve nija-bhakti karena prakāśe
tāhāra darśane ‘vaiṣṇava’ haya sarva-deśe
Synonyms: 
sei jīve — in that living being; nija-bhakti — His own devotion; karena prakāśe — manifests directly; tāhāra darśane — by seeing such an empowered devotee; vaiṣṇava — devotees of Kṛṣṇa; haya — become; sarva-deśe — in all other countries.
Translation: 
Thus He empowered living beings [His pure devotees] by manifesting in them so much of His own devotion that people in all other countries became devotees by seeing them.
Purport: 

As stated in the Caitanya-caritāmṛta (Antya 7.11):

kali-kālera dharma — kṛṣṇa-nāma-saṅkīrtana
kṛṣṇa-śakti vinā nahe tāra pravartana

Unless one is empowered by the Supreme Personality of Godhead, Śrī Caitanya Mahāprabhu, one cannot spread the holy names of the Hare Kṛṣṇa mahā-mantra throughout the world. Persons who do so are empowered. Therefore they are sometimes called āveśa-avatāras, or empowered incarnations, for they are endowed with the power of Śrī Caitanya Mahāprabhu.