On another occasion, Śrī Caitanya Mahāprabhu once inquired from Haridāsa Ṭhākura, who was known as Brahma Haridāsa, how the yavanas, or persons bereft of Vedic culture, would be delivered in Kali-yuga. Haridāsa Ṭhākura replied that their deliverance would be possible if they very loudly chanted the Hare Kṛṣṇa mantra, for hearing the Hare Kṛṣṇa mantra chanted loudly, even with but little realization, would help them.
(Sri Caitanya Caritamrta---3:3---summary).

After describing this incident, the author of the Caitanya-caritāmṛta also describes how Haridāsa Ṭhākura was tested at Benāpola, a village near Śāntipura. A person named Rāmacandra Khān, who was envious of Haridāsa Ṭhākura, sent a professional prostitute to attempt to defame him, but by the mercy of Haridāsa Ṭhākura, even the prostitute was delivered. Because of offending a pure Vaiṣṇava, Rāmacandra Khān was later cursed by Nityānanda Prabhu and ruined.
(Sri Caitanya Caritamrta---3:3---summary).

A person who is not purified by the prescribed process of saṁskāra is called asaṁskṛta, but if one remains kriyā-hīna even after being purified by initiation—in other words, if one fails to actually apply the principles of purity in his life—he remains an unpurified mleccha or yavana. On the other hand, we find that Haridāsa Ṭhākura, although born in a mleccha or yavana family, became Nāmācārya Haridāsa Ṭhākura because he performed the nāma-yajña a minimum of 300,000 times every day.
(Sri Caitanya Caritamrta---3:3:124---purport).

Haridāsa Ṭhākura was the ideal spiritual master because he regularly chanted on his beads a prescribed number of times. Indeed, he was chanting the holy name of the Lord 300,000 times a day. Similarly, the members of the Kṛṣṇa consciousness movement chant a minimum of sixteen rounds a day, which can be done without difficulty, and at the same time they must preach the cult of Caitanya Mahāprabhu according to the gospel of Bhagavad-gītā As It Is. One who does so is quite fit to become a spiritual master for the entire world.
(Sri Caitanya Caritamrta---3:4;103---purport).

Haridāsa Ṭhākura is known as nāmācārya because it is he who preached the glories of chanting hari-nāma, the holy name of God. By using the words tomāra avatāra ("your incarnation"), Śrī Caitanya Mahāprabhu confirms that Haridāsa Ṭhākura is the incarnation of Lord Brahmā. Śrīla Bhaktisiddhānta Sarasvatī Ṭhākura says that advanced devotees help the Supreme Personality of Godhead in His mission and that such devotees or personal associates incarnate by the will of the Supreme Lord.
(Sri Caitanya Caritamrta---3:11:25---purport).