योगवासिष्ठः yogavāsiṣṭhaḥ - book-1, chapter-29, verse-21

नीहारं हृदयाटव्यां मनस्तिमिरमाशु मे ।
केन विज्ञानदीपेन भिन्धि तत्त्वविदांवर ॥ २१ ॥

nīhāraṃ hṛdayāṭavyāṃ manastimiramāśu me ,
kena vijñānadīpena bhindhi tattvavidāṃvara 21

21. nīhāram hṛdaya-āṭavyām manas-timiram āśu me |
kena vijñāna-dīpena bhindhi tattva-vid-ām-vara ||

21. tattva-vid-ām-vara me hṛdaya-āṭavyām nīhāram
manas-timiram āśu kena vijñāna-dīpena bhindhi

21. O best among the knowers of truth (tattvavit)! Please quickly dispel for me, with what lamp of knowledge (vijñāna-dīpa), this fog — the darkness of the mind (manas) — in the forest of my heart.

Words meanings summery:

• नीहारम् (nīhāram) - the metaphorical fog of ignorance or mental obscurity (fog, mist, dew)

• हृदय-आटव्याम् (hṛdaya-āṭavyām) - in the metaphorical wilderness of one's inner being (in the forest of the heart)

• मनस्-तिमिरम् (manas-timiram) - the obscurity or ignorance residing in the mind (manas) (darkness of the mind)

• आशु (āśu) - quickly, swiftly, immediately

• मे (me) - for me (to me, my, for me)

• केन (kena) - by what, with what

• विज्ञान-दीपेन (vijñāna-dīpena) - by the illuminating power of wisdom (vijñāna) (by the lamp of knowledge)

• भिन्धि (bhindhi) - dispel, remove (the darkness) (break, cleave, dispel)

• तत्त्व-विद्-आम्-वर (tattva-vid-ām-vara) - addressing a revered teacher or sage who possesses ultimate knowledge (tattva) (O best among the knowers of truth)

Words meanings and morphology

नीहारम् (nīhāram) - the metaphorical fog of ignorance or mental obscurity (fog, mist, dew)

(noun)

Accusative, masculine, singular of nīhāra

nīhāra - fog, mist, dew, hoarfrost

हृदय-आटव्याम् (hṛdaya-āṭavyām) - in the metaphorical wilderness of one's inner being (in the forest of the heart)

(noun)

Locative, feminine, singular of hṛdaya-āṭavī

hṛdaya-āṭavī - forest of the heart

Compound type : tatpurusha (hṛdaya+āṭavī)

• hṛdaya – heart, mind, core
  noun (neuter)
• āṭavī – forest, wilderness, jungle
  noun (feminine)

मनस्-तिमिरम् (manas-timiram) - the obscurity or ignorance residing in the mind (manas) (darkness of the mind)

(noun)

Accusative, neuter, singular of manas-timira

manas-timira - darkness of the mind

Compound type : tatpurusha (manas+timira)

• manas – mind (manas), intellect, understanding
  noun (neuter)
• timira – darkness, gloom, eye disease causing dim vision
  noun (neuter)

आशु (āśu) - quickly, swiftly, immediately

(indeclinable)

Note: Adverb

मे (me) - for me (to me, my, for me)

(pronoun)

Dative, singular of asmad

asmad - I, we

Note: Optional dative/genitive enclitic form

केन (kena) - by what, with what

(pronoun)

Instrumental, masculine, singular of kim

kim - who, what, which

Note: Agrees with 'vijñāna-dīpena'

विज्ञान-दीपेन (vijñāna-dīpena) - by the illuminating power of wisdom (vijñāna) (by the lamp of knowledge)

(noun)

Instrumental, masculine, singular of vijñāna-dīpa

vijñāna-dīpa - lamp of special knowledge, lamp of wisdom

Compound type : tatpurusha (vijñāna+dīpa)

• vijñāna – special knowledge, wisdom, understanding (vijñāna)
  noun (neuter)
  verbal noun
  from vi-jñā + lyuṭ
  Prefix: vi
  Root: jñā (class 9)
• dīpa – lamp, light, illuminator
  noun (masculine)
  from dīp + a
  Root: dīp (class 4)

भिन्धि (bhindhi) - dispel, remove (the darkness) (break, cleave, dispel)

(verb)

2nd person , singular, active, imperative (loṭ) of bhid

Imperative Active

2nd person singular, Parasmaipada

Root: bhid (class 7)

तत्त्व-विद्-आम्-वर (tattva-vid-ām-vara) - addressing a revered teacher or sage who possesses ultimate knowledge (tattva) (O best among the knowers of truth)

(noun)

Vocative, masculine, singular of tattva-vid-ām-vara

tattva-vid-ām-vara - best among the knowers of truth

Compound type : tatpurusha (tattva+vid+vara)

• tattva – truth, reality, principle, essence
  noun (neuter)
• vid – knower, one who knows
  noun (masculine)
  agent noun
  from √vid (to know)
  Root: vid (class 2)
• vara – best, excellent, supreme, boon
  noun (masculine)
  from √vṛ (to choose)
  Root: vṛ (class 9)