योगवासिष्ठः yogavāsiṣṭhaḥ - book-3, chapter-21, verse-18

पूर्वं न संभवत्येव स्मरणीयमिति स्वयम् ।
पद्मजादित्वमायाति चैतन्यस्य तथास्थितेः ॥ १८ ॥

pūrvaṃ na saṃbhavatyeva smaraṇīyamiti svayam ,
padmajāditvamāyāti caitanyasya tathāsthiteḥ 18

18. pūrvam na saṃbhavati eva smaraṇīyam iti svayam
padmajāditvam āyāti caitanyasya tathāsthiteḥ

18. pūrvam smaraṇīyam iti svayam eva na saṃbhavati.
tathāsthiteḥ caitanyasya padmajāditvam āyāti.

18. Indeed, it is not possible for him to remember his past directly. The consciousness (caitanya) attains the state of being Brahmā (padmajāditva) due to its being in such a condition.

Words meanings summery:

• पूर्वम् (pūrvam) - his prior memory (before, prior, former, previously)

• न (na) - not

• संभवति (saṁbhavati) - is possible, occurs, exists

• एव (eva) - indeed, only, alone, certainly

• स्मरणीयम् (smaraṇīyam) - that which is to be remembered (to be remembered, memorable)

• इति (iti) - thus, so, indicating a quote or conclusion

• स्वयम् (svayam) - by himself, personally

• पद्मजादित्वम् (padmajāditvam) - the state of being Brahmā, the state of being the lotus-born one

• आयाति (āyāti) - comes, attains, reaches

• चैतन्यस्य (caitanyasya) - of consciousness (caitanya), of the sentient principle

• तथास्थितेः (tathāsthiteḥ) - due to such a state, from such a condition

Words meanings and morphology

पूर्वम् (pūrvam) - his prior memory (before, prior, former, previously)

(indeclinable)

Note: Adverbial usage here, modifying the act of remembering.

न (na) - not

(indeclinable)

Note: Negation.

संभवति (saṁbhavati) - is possible, occurs, exists

(verb)

3rd person , singular, active, present (laṭ) of saṃbhū

from sam- + bhū (to be)

Prefix: sam

Root: bhū (class 1)

एव (eva) - indeed, only, alone, certainly

(indeclinable)

Note: Emphatic.

स्मरणीयम् (smaraṇīyam) - that which is to be remembered (to be remembered, memorable)

(adjective)

Nominative, neuter, singular of smaraṇīya

smaraṇīya - to be remembered, memorable, worthy of remembrance

Gerundive

from smṛ (to remember) + anīya

Root: smṛ (class 1)

Note: Here it acts as the subject 'that which is to be remembered'.

इति (iti) - thus, so, indicating a quote or conclusion

(indeclinable)

Note: Introduces or emphasizes the preceding statement/idea.

स्वयम् (svayam) - by himself, personally

(indeclinable)

Note: Emphasizes the agent, referring to the Brahmin himself.

पद्मजादित्वम् (padmajāditvam) - the state of being Brahmā, the state of being the lotus-born one

(noun)

Accusative, neuter, singular of padmajāditva

padmajāditva - the state of being the lotus-born (Brahmā) and primal/foremost

from padmaja + ādi + tva (abstract suffix)

Compound type : tatpuruṣa (padmaja+ādi+tva)

• padmaja – lotus-born (an epithet of Brahmā)
  noun (masculine)
  from padma (lotus) + ja (born)
  Root: jan (class 4)
• ādi – beginning, primary, first, etcetera
  noun (masculine)
• tva – abstract suffix, -ness, -hood
  indeclinable

Note: Object of 'āyāti'.

आयाति (āyāti) - comes, attains, reaches

(verb)

3rd person , singular, active, present (laṭ) of āyā

from ā- + yā (to go)

Prefix: ā

Root: yā (class 2)

चैतन्यस्य (caitanyasya) - of consciousness (caitanya), of the sentient principle

(noun)

Genitive, neuter, singular of caitanya

caitanya - consciousness, intelligence, sentient principle, spirit

from cetana + ya (abstract suffix)

Root: cit (class 1)

Note: Possessive, 'of consciousness'.

तथास्थितेः (tathāsthiteḥ) - due to such a state, from such a condition

(noun)

Ablative, feminine, singular of tathāsthiti

tathāsthiti - such a state, such a condition, being in such a condition

from tathā (thus) + sthiti (state, condition)

Compound type : karmadhāraya (tathā+sthiti)

• tathā – thus, so, in such a manner
  indeclinable
• sthiti – state, condition, existence, remaining
  noun (feminine)
  from sthā (to stand) + ti
  Root: sthā (class 1)

Note: Indicates cause/reason.