Bhagavad Gita Chapter 17 Verse 28
भगवद् गीता अध्याय 17 श्लोक 28

अश्रद्धया हुतं दत्तं तपस्तप्तं कृतं च यत्।
असदित्युच्यते पार्थ न च तत्प्रेत्य नो इह।।17.28।।



हिंदी अनुवाद - स्वामी तेजोमयानंद
।।17.28।। हे पार्थ  जो यज्ञ? दान? तप और कर्म अश्रद्धापूर्वक किया जाता है? वह असत् कहा जाता है वह न इस लोक में (इह) और न मरण के पश्चात् (उस लोक में) लाभदायक होता है।।


Brahma Vaishnava Sampradaya - Commentary

Since the performance of  all  Vedic  activities  are  exclusively  for  the
propitiation and worship  of  the  Supreme  Lord  Krishna  and  any  of  His
avatars or authorised incarnations and expansions such activities are  known
as SAT. The Supreme Lord is  celebrated  and  glorified  by  His  triplicate
names of OM TAT SAT. The Vedic hymns and mantras gain power when OM TAT  SAT
are vibrated at their commencement and lose power if  they  are  omitted  at
the end. Any hymns, chants or mantras sacred  incantations  recited  without
first uttering OM TAT SAT are known as a-sura or  void  of  light  and  non-
luminous.  Also  recitation  of   OM   TAT   SAT   without   comprehensively
understanding its  meaning  bestows  little  faith  and  has  meagre  value.
Similarly chanting Vedic mantras without knowing their meaning is  worthless
because Vedic mantras protect those who know the meaning  reciting  them  as
well as those who know the meaning and hear them and because  of  this  they
are known as mantras. Therefore an aspirant for  advancement  should  always
be cognizant of the meaning of the  mantras  during  chanting  and  hearing.
This has been revealed in the Paingi scripture.  The  performance  of  Vedic
activities and the chanting  of  Vedic  mantras  while  cognizant  of  their
meaning without any expectation of reward are known as sura or luminous  and
enlightened. Therefore only activities performed in devotion  and  connected
to the Supreme Lord are deemed SAT  and  are  of  the  nature  of  perpetual
goodness. All other actions contrary to this are known as asat.

Activities in raja guna the mode of passion are also included  as  asat  due
to the defect of self-motivated desires  which  keeps  one  in  samsara  the
perpetual cycle of birth and  death.  Actions  in  tama  guna  the  mode  of
ignorance are situated in asat as well due to a comatose state of  nescience
and causes one to descend into the inferior hellish worlds.

Only by being established and situated in sattva guna the mode  of  goodness
is a jiva or embodied being redeemed which leads to atma tattva  realisation
of the immortal soul, moksa freedom from material  existence  and  attaining
communion with the Supreme Lord. Therefore to receive salvation  one  should
eternally perform prescribed Vedic  actions  in  sattva  guna  which  always
pleases the Supreme Lord Krishna.