Bhagavad Gītā Chapter 4, Verse 8: Krishna to Arjuna — Jñāna-Karma-Sannyāsa-Yoga

Bhāṣyakāra purports

• Śaṅkaraadvaita

  For the protection (paritrāṇa) of those established in the right path (sanmārga-stha) and the destruction of the sinful (pāpakārin), Īśvara — who in reality undergoes no true birth — appears age after age through māyā. The third purpose subsumes both: by removing adharma and reinstating Vedic dharma, the apparent Lord restores the very conditions under which jñāna can arise in qualified seekers. The avatāra is thus not a cosmic rescue but an epistemological clearing — the real work remains the seeker's own discrimination.

  divergence: parirakṣaṇāya sanmārgasthānām ... dharmasya samyak sthāpanaṃ tadartham

• Rāmānujaviśiṣṭādvaita

  The sādhus here are specifically the Vaiṣṇava devotees (mat-samāśrayana-pravṛtta) who, unable to bear even a moment's separation from Bhagavān's form and deeds (nāma-karma-svarūpa), become undone in body and limb — for their paritrāṇa (rescue from that unbearable longing), Bhagavān descends with his form, speech, and glance as nourishment. The duṣkṛtas are not merely sinners but those opposed to this devotional dharma; their destruction too serves the bhaktas' welfare. Descent is an act of love in every age, unrestricted to any particular yuga.

  divergence: aṇumātrakālam api kalpasahasraṃ manvānāḥ praśithilasarvagātrā ... mat-svarūpa-ceṣṭitāvalokana-alāpādi-dānena teṣāṃ paritrāṇāya

• Madhvadvaita

  There is no rule that birth alone accomplishes protection and destruction; Hari acts by his own svabhāva (intrinsic nature) and by līlā (spontaneous play), entirely free from compulsion. Like a child at sport — yet the child is Anantavīrya, of boundless power — he who is pūrṇa (utterly full) and has nothing to gain still undertakes all action; the seers who know the highest and the lowest (parāvara-jña) declare him to act out of apparent contradiction, which is itself the proof of his absolute independence (svātantrya). Paritrāṇa and vināśa are the sport of the supremely full One.

  divergence: na janmanaiva paritrāṇādi kāryam iti niyamaḥ ... līlayā svabhāvena ca yatheiṣṭacārī ... pūrṇo'yam asya na kiñcid āpyam tathāpi sarvāḥ kurute pravṛttīḥ

• Vallabhaśuddhādvaita

  Verse 4.7 named the when; 4.8 names the purpose — but in Puṣṭi-mārga the tripartite purpose is entirely Kṛṣṇa's own prasāda-impulse: he protects the dharma-vat (those who possess dharma), destroys the duṣkṛt (those whose karma is corrupt), and does so yuge yuge without calendrical constraint. Even the apparent severity of destruction carries no pitilessness (nairghṛṇya): as a mother who both caresses and strikes her infant acts without cruelty, so Maheśa — the supreme controller of virtue and fault — acts solely from niyantṛ-love. The descent is both when-he-wills and how-he-wills.

  divergence: nāvatārakālaniyama ity etadarthaṃ yuge yuge uktam ... lālane tāḍane mātur nākāruṇyaṃ yathārbhake

• Śrīdharabhakti

  The question 'for what purpose?' (kim-artham) is answered in three clean steps: protection of the sādhus (those who walk svadharma), destruction of the duṣkṛtas (evil-doers), and through both acts together the firm establishment of dharma (dharmaṃ sthīrīkartum). Śrīdhara, like Vallabha, adds the mother-analogy to remove any charge of cruelty against the destroyer-function. The descent is occasioned not by yuga-sequence but by the arising of the need (tat-tad-avasare) — an on-demand, responsive avatāra theology.

  divergence: sādhurakṣaṇena duṣṭavadhena ca dharmaṃ sthīrīkartuṃ yuge yuge tattad-avasare sambhavāmīty arthaḥ

• Madhusūdanaadvaita-bhakti

  Madhusūdana opens with a dialectical challenge: would not the very occasion of dharma's decline and adharma's rise — the pretext for avatāra — make the descent itself a source of harm? He refutes this by unpacking the three purposes as a single coherent act: paritrāṇa means protecting from every side (paritaḥ sarvato rakṣaṇam) the sādhus on the Vedic path now imperiled; vināśa removes those actively opposing that path; and dharma-saṃsthāpana is precisely the preservation of veda-mārga by the removal of adharma. The avatāra is therapeutically complete — diagnosis, excision, and restoration in one descent.

  divergence: paritrāṇāya paritaḥ sarvato rakṣaṇāya ... dharmasya samyag adharma-nivāraṇena sthāpanaṃ veda-mārga-parirakṣaṇaṃ dharmasaṃsthāpanam