17-19

मूढ ग्राहेण आत्मनो यत् पीडया क्रियते तपः ।
परस्योत्सादनार्थम् वा तत् तामसम् उदाहृतम् ॥ १९ ॥

mUDha grAheNa Atmano yat pIDayA kriyate tapaH |
parasyotsAdanArtham vA tat tAmasam udAhRtam || 19 ||

यत् तपः क्रियते [yat tapaH kriyate] Discipline that’s practiced मूढ ग्राहेण [mUDha grAheNa] with confused perceptions आत्मनः पीडया [AtmanaH pIDayA] to torment oneself, वा [vA] or परस्य उत्सादनार्थम् [parasya utsAdanArtham] practiced in order to put aside others तत् उदाहृतम् [tat udAhRtam] - such discipline is said to be तामसम् [tAmasam] in the quality of tamas .

People with confused perceptions do not make the right judgement. In this confusion, they apply themselves without considering the limits of their abilities. Such discipline is done for self-torment. This, along with any discipline that’s meant to put aside others is said to be in the quality of tamas .

Next, the Lord goes ahead to describe the three ways in which things can be given - the three forms of charity.