It is from Padma Purana, Brahma Khanda, 25th Chapter, verses 15-20.
The censure of the good causes a great sin against the name (of
Visnu). How does (i.e. would) it tolerate the censure of those on
account of whom it has become famous? He indeed does ill to the name
of Visnu, who, in this world, would regard all (things) about the
auspicious Sri Visnu, as different from his own mind. He who does not
disrespect his preceptor, who does not censure sacred texts, who does
not look upon Visnu's name as (merely) glorificatory, who does not
have a wicked idea about (i.e. to look upon) name (as) sinful, has
purification by means of restraints. Indifference to religious vows,
sacrifice (for others), offering oblations, all good actions is also a
fault. Not having faith, turning away one's face, not listening to
advice is also a sin against the auspicious name. He, the mean man,
who, even after hearing the greatness of (Visnu's) name, remains
without love for it, and is only intent upon 'I', 'mine' etc. (i.e. is
selfish), has committed sin against the name (of Visnu). O Narada,
Siva, with grace, told the sages and me the great name of the lord,
bringing happiness. It should always be carefully preserved. They who
even knowing (the importance of name), do not suddenly avoid the ten
sins against the name, are like children, who being angry, afflict
their mother. Being free from sins, always mutter the name (of Visnu).
O divine sage, due to name only you will accomplish everything and not
by any other means.
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