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).

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).

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).

The holy name has to be chanted to please the Supreme Lord, and not for any sense gratification or professional purpose. If this pure mentality is there, then even though a person is born of a low family, such as a dog-eater's, he is so glorious that not only has he purified himself, but he is quite competent to deliver others. He is competent to speak on the importance of the transcendental name, just as Ṭhākura Haridāsa did. He was apparently born in a family of Muhammadans, but because he was chanting the holy name of the Supreme Lord offenselessly, Lord Caitanya empowered him to become the authority, or ācārya, of spreading the name. It did not matter that he was born in a family which was not following the Vedic rules and regulations. Caitanya Mahāprabhu and Advaita Prabhu accepted him as an authority because he was offenselessly chanting the name of the Lord.
(Srimad Bhagavatam--3:33:7--purport).

When one is free from all ten of these offenses in chanting the holy name of God, he develops the ecstatic bodily features called pulakāśru. Pulaka means "symptoms of happiness," and aśru means "tears in the eyes." The symptoms of happiness and tears in the eyes must appear in a person who has chanted the holy name offenselessly. Here in this verse it is stated that those who have actually developed the symptoms of happiness and tears in the eyes by chanting the glories of the Lord are eligible to enter the kingdom of God. In the Caitanya-caritāmṛta it is said that if one does not develop these symptoms while chanting Hare Kṛṣṇa, it is to be understood that he is still offensive. Caitanya-caritāmṛta suggests a nice remedy in this connection. There it is said in verse 31, Chapter Eight, of Ādi-līlā, that if anyone takes shelter of Lord Caitanya and just chants the holy name of the Lord, Hare Kṛṣṇa, he becomes freed from all offenses.
(Srimad Bhagavatam--3:15:25--purport).