Shiva Purana

siva.sh/siva-purana/uma-samhita/12/50

न चास्ति तत्सुखं लोके यद्विना तपसा किल।। तपसैव सुखं सर्वमिति वेदविदो विदुः ।। ५० ।।

sanskrit

There is no happiness in the world that can be gained without penance. The knowers of the Vedas understand that all happiness is attained through penance alone.

english translation

na cAsti tatsukhaM loke yadvinA tapasA kila|| tapasaiva sukhaM sarvamiti vedavido viduH || 50 ||

hk transliteration by Sanscript