When Lord Caitanya was born during the lunar eclipse, all India was roaring with the holy sound of Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare. These sixteen names of the Lord are mentioned in many Purāṇas and Upaniṣads, and they are described as the Tāraka-brahma nāma of this age. It is recommended in the śāstras that offenseless chanting of these holy names of the Lord can deliver a fallen soul from material bondage. There are innumerable names of the Lord both in India and outside, and all of them are equally good because all of them indicate the Supreme Personality of Godhead. But because these sixteen are especially recommended for this age, people should take advantage of them and follow the path of the great ācāryas who attained success by practicing the rules of the śāstras (revealed scriptures).
(Srimad Bhagavatam-----introduction).

There is nothing in the world with which the Lord is disconnected. The only thing we must learn is to excavate the source of connection and thus be linked with Him by offenseless service. We can be connected with Him by the transcendental sound representation of the Lord. The holy name of the Lord and the Lord Himself are identical, and one who chants the holy name of the Lord in an offenseless manner can at once realize that the Lord is present before him. Even by the vibration of radio sound, we can partially realize sound relativity, and by resounding the sound of transcendence we can verily feel the presence of the Lord. In this age, when everything is polluted by the contamination of Kali, it is instructed in the scriptures and preached by Lord Śrī Caitanya Mahāprabhu that by chanting the holy name of the Lord, we can at once be free from contamination and gradually rise to the status of transcendence and go back to Godhead. The offenseless chanter of the holy name of the Lord is as auspicious as the Lord Himself, and the movement of pure devotees of the Lord all over the world can at once change the troublesome face of the world. Only by the propagation of the chanting of the holy name of the Lord can we be immune from all effects of the age of Kali.
(Srimad Bhagavatam-----1:16:32-33-----purport).

In his Anubhāṣya, Śrī Bhaktisiddhānta Sarasvatī Gosvāmī says that the actual effect that will be visible as soon as one achieves transcendental knowledge is that he will immediately become free from the clutches of māyā and fully engage in the service of the Lord. Unless one serves the Supreme Personality of Godhead Mukunda, one cannot become free from fruitive activities under the external energy. However, when one chants the holy name of the Lord offenselessly, one can realize a transcendental position that is completely aloof from the material conception of life. Rendering service to the Lord, a devotee relates to the Supreme Personality of Godhead in one of five relationships—namely, śānta, dāsya, sakhya, vātsalya or mādhurya—and thus he relishes transcendental bliss in that relationship. Such a relationship certainly transcends the body and mind. When one realizes that the holy name of the Lord is identical with the Supreme Person, he becomes completely eligible to chant the holy name of the Lord. Such an ecstatic chanter and dancer must be considered to have a direct relationship with the Lord.
(Sri Caitanya Caritamrta-----1:7:73-----purport).

In this age, people are prepared to argue that they can understand that which is beyond their limited knowledge and perception through so-called scientific observations and experiments, not knowing that actual truth comes down to man from authorities. This argumentative attitude is against the Vedic principles, and it is very difficult for one who adopts it to understand that the holy name of Kṛṣṇa is as good as Kṛṣṇa Himself. Since Kṛṣṇa and His holy name are identical, the holy name is eternally pure and beyond material contamination. It is the Supreme Personality of Godhead as a transcendental vibration. The holy name is completely different from material sound, as confirmed by Narottama dāsa Ṭhākura: golokera prema-dhana, hari-nāma-saṅkīrtana. The transcendental vibration of hari-nāma-saṅkīrtana is imported from the spiritual world. Thus although materialists who are addicted to experimental knowledge and the so-called "scientific method" cannot place their faith in the chanting of the Hare Kṛṣṇa mahā-mantra, it is a fact that simply by chanting the Hare Kṛṣṇa mantra offenselessly one can be freed from all subtle and gross material conditions.
(Sri Caitanya Caritamrta-----1:7:74-----purport).

A pure devotee of the Lord does not commit any offense while chanting the holy name of the Lord. There are ten different offenses in the chanting of the holy name of the Lord. To chant the holy name under the direction of a pure devotee is offenseless chanting. Offenseless chanting of the holy name of the Lord is transcendental, and, therefore, such chanting can at once purify one from the effects of all kinds of previous sins. This offenseless chanting indicates that one has fully understood the transcendental nature of the holy name and has thus surrendered unto the Lord.
(Srimad Bhagavatam-----1:18:19-----purport).

By offenseless chanting and hearing of the holy name of the Lord, one becomes acquainted with the transcendental form of the Lord, and then with the attributes of the Lord, and then with the transcendental nature of His pastimes, etc. Here it is mentioned that one should constantly chant the holy name of the Lord after hearing it from authorities. This means that hearing from the authorities is the first essential. Hearing of the holy name gradually promotes one to the stage of hearing about His form, about His attributes, His pastimes and so on, and thus the necessity of the chanting of His glories develops successively. This process is recommended not only for the successful execution of devotional service, but also even for those who are materially attached. According to Śrī Śukadeva Gosvāmī, this way of attaining success is an established fact, concluded not only by him, but also by all other previous ācāryas. Therefore, there is no need of further evidence. The process is recommended not only for the progressive students in different departments of ideological success, but also for those who are already successful in their achievement as fruitive workers, as philosophers or as devotees of the Lord. Śrīla Jīva Gosvāmī instructs that chanting of the holy name of the Lord should be loudly done, and it should be performed offenselessly as well, as recommended in the Padma Purāṇa.
(Srimad Bhagavatam-----2:1:11-----purport).

A sincere student aurally receives the holy name from the spiritual master, and after being initiated he follows the regulative principles given by the spiritual master. When the holy name is properly served in this way, automatically the spiritual nature of the holy name spreads; in other words, the devotee becomes qualified in offenselessly chanting the holy name. When one is completely fit to chant the holy name in this way, he is eligible to make disciples all over the world, and he actually becomes jagad-guru. Then the entire world, under his influence, begins to chant the holy names of the Hare Kṛṣṇa mahā-mantra. Thus all the disciples of such a spiritual master increase in attachment for Kṛṣṇa, and therefore he sometimes cries, sometimes laughs, sometimes dances and sometimes chants. These symptoms are very prominently manifest in the body of a pure devotee. Sometimes when our students of the Kṛṣṇa consciousness movement chant and dance, even in India people are astonished to see how these foreigners have learned to chant and dance in this ecstatic fashion. As explained by Caitanya Mahāprabhu, however, actually this is not due to practice, for without extra endeavor these symptoms become manifest in anyone who sincerely chants the Hare Kṛṣṇa mahā-mantra.
(Sri Caitanya Caritamrta-----1:7:83-----purport).

One must come to the understanding that the holy name of the Lord and the Supreme Personality of Godhead Himself are identical. One cannot reach this conclusion unless one is offenseless in chanting the holy name. By our material calculation we see a difference between the name and the substance, but in the spiritual world the Absolute is always absolute: the name, form, qualities and pastimes of the Absolute are all as good as the Absolute Himself. Thus one is understood to be an eternal servant of the Supreme Personality of Godhead if he considers himself an eternal servant of the holy name and in this spirit distributes the holy name to the world. One who chants in that spirit, without offenses, is certainly elevated to the platform of understanding that the holy name and the Personality of Godhead are identical.
(Sri Caitanya Caritamrta-----1:8:16-----purport).

Śrīla Jīva Gosvāmī instructs that chanting of the holy name of the Lord should be loudly done, and it should be performed offenselessly as well, as recommended in the Padma Purāṇa. One can deliver himself from the effects of all sins by surrendering himself unto the Lord. One can deliver himself from all offenses at the feet of the Lord by taking shelter of His holy name. But one cannot protect himself if one commits an offense at the feet of the holy name of the Lord.
(Srimad Bhagavatam-----2:1:11-----purport).

To associate with the holy name and chant the holy name is to associate with the Personality of Godhead directly. In the Bhakti-rasāmṛta-sindhu it is clearly said, sevonmukhe hi jihvādau svayam eva sphuraty adaḥ (Brs. 1.2.234). The holy name becomes manifest when one engages in the service of the holy name. This service in a submissive attitude begins with one's tongue. Sevonmukhe hi jihvādau: One must engage his tongue in the service of the holy name. Our Kṛṣṇa consciousness movement is based on this principle. We try to engage all the members of the Kṛṣṇa consciousness movement in the service of the holy name. Since the holy name and Kṛṣṇa are nondifferent, the members of the Kṛṣṇa consciousness movement not only chant the holy name of the Lord offenselessly, but also do not allow their tongues to eat anything that is not first offered to the Supreme Personality of Godhead. The Supreme Lord declares:
patraṁ puṣpaṁ phalaṁ toyaṁ yo me bhaktyā prayacchati
tad ahaṁ bhakty-upahṛtaṁ aśnāmi prayatātmanaḥ
"If one offers Me with love and devotion a leaf, a flower, a fruit or water, I will accept it." (B.G.9:26) Therefore the International Society for Krishna Consciousness has many temples all over the world, and in each and every temple the Lord is offered these foods. On the basis of His demands, the devotees chant the holy name of the Lord offenselessly and never eat anything that is not first offered to the Lord. The functions of the tongue in devotional service are to chant the Hare Kṛṣṇa mahā-mantra and eat prasādam that is offered to the Lord.
(Sri Caitanya Caritamrta-----1:8:16-----purport).

The chanting of the Hare Kṛṣṇa mantra is recommended even for persons who commit offenses, because if they continue chanting they will gradually chant offenselessly. By chanting the Hare Kṛṣṇa mantra without offenses, one increases his love for Kṛṣṇa. As stated by Śrī Caitanya Mahāprabhu, premā pum-artho mahān: one's main concern should be to increase one's attachment to the Supreme Personality of Godhead and to increase one's love for Him.
(Srimad Bhagavatam-----6:3:24-----purport).

The process of devotional service—beginning with chanting and hearing—is called sādhana-bhakti. This includes the regulative principles that are intended to awaken one to devotional service. Devotional service is always dormant in everyone's heart, and by the offenseless chanting of the holy names of the Lord, one's original dormant Kṛṣṇa consciousness is awakened. This awakening to Kṛṣṇa consciousness is the beginning of sādhana-bhakti. This can be divided into many different parts, including faith, association with devotees, initiation by the spiritual master, engagement in devotional service under the instructions of a spiritual master, steadiness in devotional service and the awakening of a taste for devotional service. In this way, one can become attached to Kṛṣṇa and His service, and when this attachment is intensified, it results in ecstatic love for Kṛṣṇa.
(Sri Caitanya Caritamrta-----2:19:177-----purport).

It is said, kali-kāle nāma-rūpe kṛṣṇa-avatāra: Kṛṣṇa descends in this Kali-yuga in the form of His holy name—Hare Kṛṣṇa, Hare Rāma. If we chant offenselessly, Rāma and Kṛṣṇa are still present in this age. The kingdom of Rāma was immensely popular and beneficial, and the spreading of this Hare Kṛṣṇa movement can immediately introduce a similar situation, even in this Kali-yuga.
(Srimad Bhagavatam-----9:10:53-----purport).

Vaiṣṇavas strictly follow the directions of the śāstras regarding how one can be liberated simply by a slight awakening of pure chanting of the holy name. Māyāvādīs cannot tolerate the statements of the śāstras about how easily liberation can be achieved, for, as stated in the Bhagavad-gītā (12.5), kleśo ‘dhikaratas teṣām avyaktāsakta-cetasām: impersonalists must work hard for many, many births, and only then will they perhaps be liberated. Vaiṣṇavas know that simply by chanting the holy name of the Lord offenselessly, one achieves liberation as a by-product. Thus there is no need to endeavor separately for liberation. Śrīla Bilvamaṅgala Ṭhākura has said, muktiḥ svayaṁ mukulitāñjali sevate "smān: liberation stands at one"s door, ready to render any kind of service, if one is a pure devotee with unflinching faith and reverence. This the Māyāvādīs cannot tolerate. Therefore the ārindā pradhāna, chief tax collector, although very learned, handsome and youthful, could not tolerate the statements of Haridāsa Ṭhākura.
(Sri Caitanya Caritamrta-----3:3:192-----purport).

"Similarly, the first hint that offenseless chanting of the Lord's holy name has awakened dissipates the reactions of sinful life immediately. And when one chants the holy name offenselessly, one awakens to service in ecstatic love at the lotus feet of Kṛṣṇa."
(Sri Caitanya Caritamrta-----3:3:185-----translation).

"Liberation is the insignificant result derived from a glimpse of the awakening of offenseless chanting of the holy name."
(Sri Caitanya Caritamrta-----3:3:186-----translation).