Valmiki Ramayana 2.103.4

इदं तेषामनाथानां क्लिष्टमक्लिष्टकर्मणाम् ।वने प्राक्केवलं तीर्थं ये ते निर्विषयीकृता:॥

idaṃ teṣāmanāthānāṃ kliṣṭamakliṣṭakarmaṇām |vane prākkevalaṃ tīrthaṃ ye te nirviṣayīkṛtā: ||

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