महाभारतः mahābhārataḥ - book-13, chapter-150, verse-3

यदा त्वस्य भवेद्बुद्धिर्धर्म्या चार्थप्रदर्शिनी ।
तदाश्वसीत धर्मात्मादृढबुद्धिर्न विश्वसेत् ॥३॥

3. yadā tvasya bhavedbuddhirdharmyā cārthapradarśinī ,
tadāśvasīta dharmātmādṛḍhabuddhirna viśvaset.

3. yadā tu asya bhavet buddhiḥ dharmyā ca arthapradarśinī
tadā aśvasīta dharmātmā adṛḍhabuddhiḥ na viśvaset

3. yadā tu asya buddhiḥ dharmyā ca arthapradarśinī bhavet,
tadā dharmātmā aśvasīta.
adṛḍhabuddhiḥ na viśvaset.

3. But when one's intellect becomes aligned with natural law (dharmya) and reveals the true purpose, then a person of righteous nature (dharmātmā) should have faith. Conversely, one with an unsteady intellect should not trust.

Words meanings summery:

• यदा (yadā) - when (when, whenever)

• तु (tu) - but (but, indeed, however)

• अस्य (asya) - one's (of him/it) (of him, of this, his)

• भवेत् (bhavet) - becomes (may be, should be, becomes)

• बुद्धिः (buddhiḥ) - intellect (intellect, understanding, reason, mind)

• धर्म्या (dharmyā) - aligned with natural law (dharmya) (righteous, lawful, just, conforming to dharma)

• च (ca) - and (and, also, moreover)

• अर्थप्रदर्शिनी (arthapradarśinī) - reveals the true purpose (showing the meaning/purpose/wealth)

• तदा (tadā) - then (then, at that time)

• अश्वसीत (aśvasīta) - should have faith (one should trust, rely on, breathe freely)

• धर्मात्मा (dharmātmā) - a person of righteous nature (dharmātmā) (one whose soul is righteousness, a righteous person)

• अदृढबुद्धिः (adṛḍhabuddhiḥ) - one with an unsteady intellect (one with an unsteady intellect, irresolute)

• न (na) - not (not, no, nor)

• विश्वसेत् (viśvaset) - should not trust (one should trust, believe, rely on)

Words meanings and morphology

यदा (yadā) - when (when, whenever)

(indeclinable)

तु (tu) - but (but, indeed, however)

(indeclinable)

अस्य (asya) - one's (of him/it) (of him, of this, his)

(pronoun)

Genitive, masculine/neuter, singular of idam

idam - this, that

भवेत् (bhavet) - becomes (may be, should be, becomes)

(verb)

3rd person , singular, active, optative (liṅ) of bhū

optative 3rd singular parasmaipada

Root: bhū (class 1)

बुद्धिः (buddhiḥ) - intellect (intellect, understanding, reason, mind)

(noun)

Nominative, feminine, singular of buddhi

buddhi - intellect, understanding, reason, mind

Root: budh (class 1)

धर्म्या (dharmyā) - aligned with natural law (dharmya) (righteous, lawful, just, conforming to dharma)

(adjective)

Nominative, feminine, singular of dharmya

dharmya - righteous, lawful, just, conforming to dharma

Gerundive

from dharma

Root: dhṛ (class 1)

Note: Modifies 'buddhiḥ'.

च (ca) - and (and, also, moreover)

(indeclinable)

अर्थप्रदर्शिनी (arthapradarśinī) - reveals the true purpose (showing the meaning/purpose/wealth)

(adjective)

Nominative, feminine, singular of arthapradarśinī

arthapradarśinī - showing the meaning/purpose/wealth

Compound type : tatpurusha (artha+pradarśin)

• artha – purpose, meaning, wealth
  noun (masculine)
  Root: arth (class 10)
• pradarśin – showing, revealing, indicating
  adjective (feminine)
  Agent noun from pra-√dṛś
  Prefix: pra
  Root: dṛś (class 1)

Note: Modifies 'buddhiḥ'.

तदा (tadā) - then (then, at that time)

(indeclinable)

अश्वसीत (aśvasīta) - should have faith (one should trust, rely on, breathe freely)

(verb)

3rd person , singular, middle, optative (liṅ) of śvas

optative 3rd singular ātmanepada

Root: śvas (class 2)

धर्मात्मा (dharmātmā) - a person of righteous nature (dharmātmā) (one whose soul is righteousness, a righteous person)

(noun)

Nominative, masculine, singular of dharmātman

dharmātman - one whose soul is righteousness, a righteous person

Compound type : bahuvrihi (dharma+ātman)

• dharma – natural law, righteousness, duty
  noun (masculine)
  Root: dhṛ (class 1)
• ātman – self, soul, spirit
  noun (masculine)
  Root: an (class 2)

अदृढबुद्धिः (adṛḍhabuddhiḥ) - one with an unsteady intellect (one with an unsteady intellect, irresolute)

(adjective)

Nominative, masculine, singular of adṛḍhabuddhi

adṛḍhabuddhi - one with an unsteady intellect, irresolute

Compound type : bahuvrihi (adṛḍha+buddhi)

• adṛḍha – not firm, unsteady, unstable
  adjective (masculine)
  Past Passive Participle (negative)
  from a (not) + dṛḍha (firm, from root dṛh)
  Root: dṛh (class 1)
• buddhi – intellect, understanding
  noun (feminine)
  Root: budh (class 1)

Note: Used substantively.

न (na) - not (not, no, nor)

(indeclinable)

विश्वसेत् (viśvaset) - should not trust (one should trust, believe, rely on)

(verb)

3rd person , singular, active, optative (liṅ) of viśvas

optative 3rd singular parasmaipada

Prefix: vi

Root: śvas (class 2)