योगवासिष्ठः yogavāsiṣṭhaḥ - book-3, chapter-22, verse-15

मांसदेहो मांसदेहेनैव संश्लेषमेष्यति ।
नतु चित्तशरीरेण व्यवहारेषु कर्मसु ॥ १५ ॥

māṃsadeho māṃsadehenaiva saṃśleṣameṣyati ,
natu cittaśarīreṇa vyavahāreṣu karmasu 15

15. māṃsadehaḥ māṃsadehena eva saṃśleṣam eṣyati
na tu cittaśarīreṇa vyavahāreṣu karmasu

15. māṃsadehaḥ māṃsadehena eva saṃśleṣam eṣyati,
na tu cittaśarīreṇa vyavahāreṣu karmasu

15. The physical body (māṃsadeha) will indeed interact only with another physical body. But the mind-body (cittaśarīra) does not engage in worldly activities (vyavahāra) or actions (karma) in the same manner.

Words meanings summery:

• मांसदेहः (māṁsadehaḥ) - the gross material body, distinct from a subtle body (physical body, fleshy body)

• मांसदेहेन (māṁsadehena) - indicating the means or instrument of contact (by the physical body, with the fleshy body)

• एव (eva) - emphasizes exclusivity; 'only with the physical body' (only, just, indeed)

• संश्लेषम् (saṁśleṣam) - physical interaction or coming together (contact, union, adherence, close connection)

• एष्यति (eṣyati) - will come into contact (will attain, will reach, will go)

• न (na) - negation of the following clause (not, no)

• तु (tu) - introduces a contrast (but, however, indeed)

• चित्तशरीरेण (cittaśarīreṇa) - by the mental or subtle vehicle of consciousness (by the mind-body, by the subtle body)

• व्यवहारेषु (vyavahāreṣu) - in the context of ordinary worldly interactions and activities (in dealings, in transactions, in worldly affairs, in conduct)

• कर्मसु (karmasu) - in the context of actions and their consequences, as part of worldly engagement (in actions, in deeds, in duties (karma))

Words meanings and morphology

मांसदेहः (māṁsadehaḥ) - the gross material body, distinct from a subtle body (physical body, fleshy body)

(noun)

Nominative, masculine, singular of māṃsadeha

māṁsadeha - fleshy body, physical body

Compound of māṃsa (flesh) and deha (body).

Compound type : tatpurusha (māṃsa+deha)

• māṃsa – flesh, meat
  noun (neuter)
• deha – body, corporeal frame
  noun (masculine)
  Root: √dih (class 4)

Note: Subject of the sentence.

मांसदेहेन (māṁsadehena) - indicating the means or instrument of contact (by the physical body, with the fleshy body)

(noun)

Instrumental, masculine, singular of māṃsadeha

māṁsadeha - fleshy body, physical body

Compound of māṃsa (flesh) and deha (body).

Compound type : tatpurusha (māṃsa+deha)

• māṃsa – flesh, meat
  noun (neuter)
• deha – body, corporeal frame
  noun (masculine)
  Root: √dih (class 4)

Note: Indicates the means of interaction.

एव (eva) - emphasizes exclusivity; 'only with the physical body' (only, just, indeed)

(indeclinable)

संश्लेषम् (saṁśleṣam) - physical interaction or coming together (contact, union, adherence, close connection)

(noun)

Accusative, masculine, singular of saṃśleṣa

saṁśleṣa - contact, union, adherence, close connection

From sam-√śliṣ (to cling to, embrace).

Prefix: sam

Root: √śliṣ (class 4)

Note: Object of eṣyati.

एष्यति (eṣyati) - will come into contact (will attain, will reach, will go)

(verb)

3rd person , singular, active, future (lṛṭ) of √iṣ

Future tense, 3rd person singular.

Root: √iṣ (class 4)

न (na) - negation of the following clause (not, no)

(indeclinable)

तु (tu) - introduces a contrast (but, however, indeed)

(indeclinable)

चित्तशरीरेण (cittaśarīreṇa) - by the mental or subtle vehicle of consciousness (by the mind-body, by the subtle body)

(noun)

Instrumental, neuter, singular of cittaśarīra

cittaśarīra - mind-body, subtle body

Compound of citta (mind, consciousness) and śarīra (body).

Compound type : karmadhāraya / tatpurusha (citta+śarīra)

• citta – mind, consciousness, thought, heart
  noun (neuter)
  Past Passive Participle
  Derived from √cit.
  Root: √cit (class 1)
• śarīra – body, form
  noun (neuter)
  Root: √śṛ (class 1)

Note: Implied agent or means for non-engagement.

व्यवहारेषु (vyavahāreṣu) - in the context of ordinary worldly interactions and activities (in dealings, in transactions, in worldly affairs, in conduct)

(noun)

Locative, masculine, plural of vyavahāra

vyavahāra - conduct, practice, usage, worldly affair, dealing, transaction

From vi-ava-√hṛ.

Prefixes: vi+ava

Root: √hṛ (class 1)

कर्मसु (karmasu) - in the context of actions and their consequences, as part of worldly engagement (in actions, in deeds, in duties (karma))

(noun)

Locative, neuter, plural of karma

karma - action, deed, work, duty, destiny, fate

From √kṛ.

Root: √kṛ (class 8)

Note: Qualifies the context of non-engagement.