Mahabharata 13.148.22

तीर्थानां गुरवस्तीर्थं शुचीनां हृदयं शुचिदर्शनानां परं ज्ञानं संतोषः परमं सुखम्

tīrthānāṃ guravastīrthaṃ śucīnāṃ hṛdayaṃ śucidarśanānāṃ paraṃ jñānaṃ saṃtoṣaḥ paramaṃ sukham

Our plain-language meaning of this verse is waiting for scholar review.