Valmiki Ramayana Aranya Kanda Sarga 9 Shloka 2
Original Shlokaअयं धर्मस्सुसूक्ष्मेण विधिना प्राप्यते महान्। निवृत्तेन तु शक्योऽयं व्यसनात्कामजादिह।।3.9.2।।
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महान् great, अयं धर्मः this righteous path, सुसूक्ष्मेण in a subtle, विधिना means, प्राप्यते is obtained, अयम् this, कामजात् born of desire, व्यसनात् by addiction, निवृत्तेन by that which is averted, इह here, शक्यः not possible.
This great path of dharma you are following now can be attained only through subtle means by one free from addiction born of passion.