Bhāṣya
अत्रोच्यते — बोधो हि नाम चैतन्यमभिप्रेतम् ; न च ज्ञानं चैतन्यम् , जन्यज्ञानस्य ज्ञेयत्वेन घटादिवज्जडत्वात् ।ज्ञेयं हि ज्ञानम् , घटज्ञानं मे जातं पटज्ञानं मे जातमिति साक्षादनुभूयमानत्वात् ।अतः तस्य अनित्यत्वेन अनात्मस्वरूपत्वेऽपि, नित्यबोधस्वरूपत्वम् आत्मन उपपद्यते ।ननु आत्मनः चेतनत्वे किं प्रमाणमिति चेत् , जगत्प्रकाश इति ब्रूमः ।जगत् प्रकाशत इति सर्वजनसिद्धम् ; तत्र ज्ञानादीनां ज्ञेयत्वेन जडत्वात् , आत्मप्रकाशेनैव जगत् प्रकाशत इति निश्चितं भवति ।आत्मा च स्वपरप्रकाशवान् सवितृप्रकाशवत् — यथा सविता स्वयं प्रकाशमानो जगदपि प्रकाशयति, तथा आत्मापीति ।अस्तु तर्हि चिद्धर्मा पुरुषः, कथमयं चित्स्वभाव इति ; न, धर्मधर्मिभावस्य अनुपपत्तेः ॥
In plain words
Here the reply is given: Pure awareness is what is truly meant by consciousness. Ordinary knowledge is not consciousness, for any generated thought is insentient like a pot, since it is experienced as an object. We directly witness our thoughts, saying 'the thought of a pot has arisen in me' or 'the thought of a cloth has arisen in me.' Therefore, even though mental cognition is impermanent and cannot be the true Self, the Self's nature is that of eternal, unbroken awareness. If you ask what proof there is that the Self is conscious, we answer: the very illumination of the world. That the world shines is universally recognized. Since individual thoughts and perceptions are insentient objects that require to be known, it is definitively established that the world is lit up entirely by the light of the Self. The Self is self-luminous and illuminates everything else, just like the sun—for as the sun shines by its own light and thereby reveals the entire world, so too does the Self. If someone argues, 'Very well, let the individual be a substance that merely possesses consciousness as a quality,' we reply: no, because a division between a substance and its qualities is logically untenable here.
Close to the Sanskrit
Here it is said: Awakening is indeed intended as consciousness; and knowledge is not consciousness, because generated knowledge is inert like a pot and so forth, due to being an object of knowledge. For knowledge is an object of knowledge, because it is directly experienced as 'knowledge of a pot has arisen in me, knowledge of cloth has arisen in me'. Therefore, although it lacks the nature of the Self owing to its impermanence, the nature of eternal awareness belongs appropriately to the Self. If it is asked, what is the proof for the conscious nature of the Self? We reply: the illumination of the world. That the world shines is established for all people; there, because cognitions and so forth are inert through being objects of knowledge, it is ascertained that the world shines precisely by the illumination of the Self. And the Self illuminates both itself and others, like the sun's illumination — just as the sun, shining by itself, illuminates the world also, so too does the Self. Let the person then be one who has consciousness as an attribute, how is this one of consciousness-nature? No, because the relation of attribute and substratum is untenable.