(From Srila Bhaktisiddhanta Sarasvati Thakura's commentary on Siksastaka, third sloka)
The devotees who chant the holy name adorned with the above mentioned qualities never abandon the devotional process received from their guru in order to adopt new and divergent views. They do not fabricate concocted verses (padavali) and chant those in place of the Harinama maha-mantra. Remaining always under the guidance of their guru, they preach the glories of the holy name, write books based on pure devotional service, and engage themselves in Harinama bhajana and kirtana.
In such activities, there is no transgression of Vaisnava humility, for the devotee always considers himself to be low and fallen. He never tries to deceive others by making a false show of humility in order to acquire wealth or cheap adoration, for he knows that such false expressions and behavior are not illustrative of genuine humility….
They never think this material world to be for their own enjoyment, but for Krsna's enjoyment. They never invent new mantras, giving up the chanting of the maha-mantra which they obtained from their guru. They do not engage in propagating new theories and opinions.