Bhagavad Gita Chapter 13 Verse 18
भगवद् गीता अध्याय 13 श्लोक 18

ज्योतिषामपि तज्ज्योतिस्तमसः परमुच्यते।
ज्ञानं ज्ञेयं ज्ञानगम्यं हृदि सर्वस्य विष्ठितम्।।13.18।।



हिंदी अनुवाद - स्वामी रामसुख दास जी ( भगवद् गीता 13.18)
।।13.18।।वह परमात्मा सम्पूर्ण ज्योतियोंका भी ज्योति और अज्ञानसे अत्यन्त परे कहा गया है। वह ज्ञानस्वरूप? जाननेयोग्य? ज्ञान(साधनसमुदाय) से प्राप्त करनेयोग्य और सबके हृदयमें विराजमान है।


English Translation of Sanskrit Commentary By Sri Shankaracharya's
13.18 Tat, that Knowable; is the jyotih, Light; api, even; jyotisam, of the lights-of the sun etc. For the lights like the sun etc. shine because they are enkindled by the light of consciousness of the Self, as is known from Upanisadic texts like, Illumined by whose light the sun shines (Tai. Br. 3.12.9.7), By Its light all this shines variously (Sv. 6.14), and from the Smrti also, as here (in the Gita) itself: That light in the sun৷৷. (15.12), etc.
It is ucyate, spoken of as; param, beyond, untouched by; tamasah, darkness; ignorance. For cheering up anyone who may become disheartened by thinking that Knowledge etc. is difficult to attain, the Lord says: It is jnanam, Knowledge-humility etc. (verse 7, etc.); jneyam, the Knowable, which has been spoken of in, I shall speak of that which is to be known (12); and jnana-gamyam, the Known. The Knowable itself is referred to as jnanagamyam, when after being known, It becomes the result of Knowledge. But when It is an object to be known, It is called jneyam. All these three which are such, visthitam, specially exist; hrdi, in the hearts, in the intellects; sarvasya, of all, of all creatures.
For these three are, indeed, perceived there.
 
This verse is begun for concluding the topic under discussion:


English Translation of Commentary  - Dr. S. Sankaranarayan
13.13-18 Jneyam etc. upto visthitam.  Beginningless is  the Supreme Brahman :  by means of the attributes  (descriptions) like these, [the Bhagavat] describes the Brahman as being not separate from the Supreme Consciousness  (or action)  expressed in every utterance and  [thus] gracing  [the seeker] to infer his [or Its] own nature.  These attributes however have already been explained.  Hence what is the use of a fruitless repetition ?


English Translation of Ramanuja's Sanskrit Commentary
13.18 This (self) alone is the light which illuminates things like the sun, a lamp, a gem etc. It is knowledge alone in the form of the effulgence of the self which illuminates a lamp, the sun etc. But a lamp etc., dispel the darkness that intervenes between the sense of sight and its subject. Their illuminating power is limited to this extent. This is said to be beyond Tamas (darkness). The term Tamas denotes Prakrti in its subtle state. The meaning is that the self transcends Prakrti. Therefore, It is to be comprehended as knowledge, i.e., to be understood as of the form of knowledge. It is attainable by means of knowledge - such as modesty etc., already described. It is present in the heart of all, i.e., It is specially settled, or present in the heart of all beings like men etc.


Transliteration Bhagavad Gita 13.18Jyotishaamapi tajjyotistamasah paramuchyate;
Jnaanam jneyam jnaanagamyam hridi sarvasya vishthitam.


Word Meanings Bhagavad Gita 13.18jyotiṣhām—in all luminarie; api—and; tat—that; jyotiḥ—the source of light; tamasaḥ—the darkness; param—beyond; uchyate—is said (to be); jñānam—knowledge; jñeyam—the object of knowledge; jñāna-gamyam—the goal of knowledge; hṛidi—within the heart; sarvasya—of all living beings; viṣhṭhitam—dwells