योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-175, verse-77

अनर्थेनाविचारेण वयः कुर्यान्न भस्मसात् ।
बोधेन ज्ञानसारेण दृश्यं कर्तव्यमात्मसात् ॥ ७७ ॥

anarthenāvicāreṇa vayaḥ kuryānna bhasmasāt ,
bodhena jñānasāreṇa dṛśyaṃ kartavyamātmasāt 77

77. anarthena avicāreṇa vayaḥ kuryāt na bhasmasāt
bodhena jñāna-sāreṇa dṛśyam kartavyam ātmasāt

77. anarthena avicāreṇa vayaḥ na bhasmasāt kuryāt
bodhena jñāna-sāreṇa dṛśyam ātmasāt kartavyam

77. One should not squander one's life in meaninglessness and thoughtlessness, reducing it to ashes. Instead, through true understanding and the essence of knowledge, one should make the phenomenal world one with the Self (ātman).

Words meanings summery:

• अनर्थेन (anarthena) - by futility, by being uselessly spent (by meaninglessness, by futility, by harm)

• अविचारेण (avicāreṇa) - by neglecting proper thought or inquiry (by thoughtlessness, by lack of consideration)

• वयः (vayaḥ) - one's life, lifespan (age, life, period of life)

• कुर्यात् (kuryāt) - one should make (or cause to become) (one should do, one should make)

• न (na) - not (not, no)

• भस्मसात् (bhasmasāt) - reduced to nothing, wasted (reduced to ashes, turned into ashes)

• बोधेन (bodhena) - through spiritual awakening or true understanding (by awakening, by understanding, by knowledge)

• ज्ञान-सारेण (jñāna-sāreṇa) - through the core or vital part of knowledge (by the essence of knowledge)

• दृश्यम् (dṛśyam) - the phenomenal world, all that is perceived (visible, to be seen, the seen, the phenomenal world)

• कर्तव्यम् (kartavyam) - should be made or caused to become (to be done, should be done, ought to be made)

• आत्मसात् (ātmasāt) - understood as non-different from the Self (ātman) (assimilated into the Self, made one with the Self)

Words meanings and morphology

अनर्थेन (anarthena) - by futility, by being uselessly spent (by meaninglessness, by futility, by harm)

(noun)

Instrumental, masculine, singular of anartha

anartha - meaninglessness, futility, misfortune, harm, uselessness

negative compound (na-artha)

Compound type : nañ-tatpuruṣa (a+artha)

• a – not, non-
  indeclinable
• artha – purpose, meaning, wealth, object, goal
  noun (masculine)

अविचारेण (avicāreṇa) - by neglecting proper thought or inquiry (by thoughtlessness, by lack of consideration)

(noun)

Instrumental, masculine, singular of avicāra

avicāra - thoughtlessness, inconsideration, lack of judgment

negative compound (na-vicāra)

Compound type : nañ-tatpuruṣa (a+vicāra)

• a – not, non-
  indeclinable
• vicāra – investigation, deliberation, consideration, judgment
  noun (masculine)
  verbal noun from vi-car (to consider, examine)
  Prefix: vi
  Root: car (class 1)

वयः (vayaḥ) - one's life, lifespan (age, life, period of life)

(noun)

Accusative, neuter, singular of vayas

vayas - age, life, youth, strength

कुर्यात् (kuryāt) - one should make (or cause to become) (one should do, one should make)

(verb)

3rd person , singular, active, optative (vidhiliṅ) of kṛ

optative

parasmaipada, root class 8

Root: kṛ (class 8)

न (na) - not (not, no)

(indeclinable)

भस्मसात् (bhasmasāt) - reduced to nothing, wasted (reduced to ashes, turned into ashes)

(indeclinable)

From bhasman (ashes) + -sāt suffix (meaning 'to make into')

बोधेन (bodhena) - through spiritual awakening or true understanding (by awakening, by understanding, by knowledge)

(noun)

Instrumental, masculine, singular of bodha

bodha - awakening, knowledge, understanding, perception

from root budh (to know, awaken)

Root: budh (class 1)

ज्ञान-सारेण (jñāna-sāreṇa) - through the core or vital part of knowledge (by the essence of knowledge)

(noun)

Instrumental, masculine, singular of jñāna-sāra

jñāna-sāra - essence of knowledge, core of knowledge

Compound

Compound type : tatpurusha (jñāna+sāra)

• jñāna – knowledge, wisdom, awareness
  noun (neuter)
  verbal noun from jñā (to know)
  Root: jñā (class 9)
• sāra – essence, core, pith, strength, best part
  noun (masculine)

दृश्यम् (dṛśyam) - the phenomenal world, all that is perceived (visible, to be seen, the seen, the phenomenal world)

(noun)

Accusative, neuter, singular of dṛśya

dṛśya - visible, to be seen, perceptible, the seen, object of sight

gerundive (future passive participle)

from root dṛś (to see), with -ya suffix

Root: dṛś (class 1)

कर्तव्यम् (kartavyam) - should be made or caused to become (to be done, should be done, ought to be made)

(adjective)

Nominative, neuter, singular of kartavya

kartavya - to be done, to be made, proper to be done

gerundive (future passive participle)

from root kṛ (to do, make) with -tavya suffix

Root: kṛ (class 8)

Note: Predicate adjective, agrees with dṛśyam.

आत्मसात् (ātmasāt) - understood as non-different from the Self (ātman) (assimilated into the Self, made one with the Self)

(indeclinable)

from ātman (Self) + -sāt suffix (meaning 'to make into')