18.3 Tyajyam etc.  The harmful :  that which is connected with sin, becuase it consists of act of injury etc.  Such an action must be relinished and not all aciton that has auspicious result.  In this way certain persons-as if they are attached  (as domesticated animals do )  to the house of the Sankhyas - think of a distinction is relinishing.  But there are other learned persons who put on the coat of the Mimamsakas and who, basing exclusively the scriptures, classify what action to be performed and what action not to be performed .  They opine :  The act of killing that constitutes the technical aspect of execution of a sacrifice is [in fact] not an act of injury at all in view of the principles, like
 
'The action intended for sacrifice is indeed known from the scripture only' - (SB, IV, i, 2)
 and  
'Therefore the act of injury known from the Vedas' etc. - (SV, I, i, 2.23)
 
For, the general rule 'Don't injure' is  annulled in  this case.  But, at the same time the Syena-sacrifice etc., is an act of killing.  Becuase,
 
'The injunctive suffix does not prescribe what falls within the purveiw of fruit of an action of the injunction.'  [SV, I, i, 2.222).
 
Therefore other [Vedic] sacrifices one should not relinish eventhough they are connected with an act of injury.