When chanting the Maha Mantra it is important to avoid these offences :
The Ten Offences to the Holy Name (From the Padma Purana by Vyasadev)
1) To blaspheme the devotees who have dedicated their lives for propagating the holy name of the Lord.
2) To consider the names of demigods like Lord Shiva or Lord Brahma to be equal to or independent of the name of the Lord Vishnu.
3) To disobey the orders of the spiritual master.
4) To blaspheme the vedic scriptures or scriptures in pursuance to the vedic version.
5) To consider the glories of chanting Hare Krishna to be an imagination.
6) To give some interpretations to the holy name of the Lord.
7) To commit sinful activities on the strength of the holy name.
8) To consider the chanting of Hare Krishna as one of the auspicious ritualistic activities which are offered in the Vedas as frutive activities (Karma kanda).
9) To instruct a faithless person about the glories of the holy name
10) To not have complete faith in the chanting of the holy name and to maintain material attachments, even after understanding so many instructions on this matter.
It is also an offense to be inattentive while chanting.
Every devotee who claims to be Vaishnava must guard against these offenses in order to quickly achieve the desired success:
Chant the Maha Mantra:
"hare krishna hare krishna krishna krishna hare hare
hare rama hare rama rama rama hare hare"
Your life will become sublime.
The Holy Name Is the Direct Path (from Sri Harinama Cintamini
(by Srila Haridas Thakur, Translated by Srila Bhaktivinoda Thakur)
77. "0 Supreme Lord, thinking how to benefit the conditioned souls, in Kali yuga You descended to this world with the holy name.
78. "You taught that nama-sankirtana (chanting of the holy name) is the yuga dharma (religion of the age). By following this direct path of chanting the holy name, the conditioned souls attain a great treasure of love for Lord Krsna.
79. "Simply by chanting or remembering the holy name the conditioned souls will become delivered.
International Society for Krishna Consciousness
Founder-Acarya: His Divine Grace
A.C. Bhaktivedanta Swami Srila Prabhupada