Bhagavad Gita Chapter 17 Verse 19
भगवद् गीता अध्याय 17 श्लोक 19

मूढग्राहेणात्मनो यत्पीडया क्रियते तपः।
परस्योत्सादनार्थं वा तत्तामसमुदाहृतम्।।17.19।।



हिंदी अनुवाद - स्वामी तेजोमयानंद
।।17.19।। जो तप मूढ़तापूर्वक स्वयं को पीड़ित करते हुए अथवा अन्य लोगों के नाश के लिए किया जाता है? वह तप तामस कहा गया है।।


Kumara Vaishnava Sampradaya - Commentary
Now Lord Krishna explains the austerities that are of tama guna or  mode  of
ignorance. The word mudha means foolish. The word grahena  means  endeavour.
Those who foolishly endeavour are the ignorant. Those who torture  and  give
pain to themselves and diabolically cause injury  and  suffering  to  others
are depraved and their dark resolves  are  at  the  pinnacle  of  nescience.
Whatever activity they enact  by  such  convoluted  resolves  regardless  of
success or failure is in the darkness of tama guna.