Medicines and all antidotes to poisonous articles, and the various acts (seen here), produce their intended results through the help of penance. The fulfilment of all purposes depends upon penance.
औषधान्यगदादीनि क्रियाश्च विविधास्तथा। तपसैव हि सिद्ध्यन्ति तपोमूलं हि साधनम्॥