Text:

श्रवणायापि बहुभिर्यो न लभ्यः शृण्वन्तोऽपि बहवो यं न विद्युः ।
आश्चर्यो वक्ता कुशलोऽस्य लब्धाश्चर्यो ज्ञाता कुशलानुशिष्टः ॥ ७ ॥

śravaṇāyāpi bahubhiryo na labhyaḥ śṛṇvanto’pi bahavo yaṃ na vidyuḥ |
āścaryo vaktā kuśalo’sya labdhāścaryo jñātā kuśalānuśiṣṭaḥ || 7 ||

7. Who cannot be attained even for hearing by many; whom, many though hearing, do not know; the expounder of him is a wonder; and able, the attainer of him; a wonder, the knower of him instructed by the able.

Shankara’s Commentary:

Of thousands who seek good, it is some one like you who becomes the knower of the atman; for, even for hearing, the atman is not attainable by many; many others, though they hear of him, do not know the atman, not being entitled, because their minds are not purified; again, the expounder of the itman is, like a wonder, some one among many, Similarly, even among many who have so heard, some one alone of many, that is able, attains the atman; the knower of the atman is a wonder—some me who is instructed by an able preceptor.