Valmiki Ramayana Yuddha Kanda Sarga 35 Shloka 22
Original Shlokaतेषुतेषुचदेशेषुपुण्येष्वेवदृढव्रतैः ।।6.35.22।। चर्यमाणंतपस्तीव्रंसन्तापयतिराक्षसान् ।
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पुण्येष्वेव at holy places दृढव्रतैः determined firmly, तेषुतेषु those, देशेषु regions चर्यमाणम् performing, तीव्रम् intense, तपः austerities, राक्षसान् Rakshasas, सन्तापयति tormenting.
"The intense austerities performed by the sages in different regions determined firmly are tormenting the Rakshasas."