Srimad Bhagavad Gita -Ramanujacharya 132

Srimad Bhagavad Gita -Ramanujacharya

Chapter-4 Jñāna Vibhāga Yogaḥ

paritrāṇāya sādhūnāṃ vināśāya ca duṣkṛtām | dharma saṃsthāpan-ārthāya saṃbhavāmi yuge yuge || 8 || 8. For the protection of the good and for the destruction of the wicked, for the establishment of Dharma, I advent myself from age to age. Commentary The 'good' are those who follow the [Vedic] Dharma, as defined above. They are the foremost among the Vaiṣṇavas, who have taken refuge in Me. While My name, pastimes and form are beyond the scope of speech and thought, these devotees cannot support or sustain themselves without My beatific vision. They regard even a moment of separation from Me as a thousand aeons. They become physically and psychologically dejected because of their separation from Me. So I take birth from age to age in the forms of gods, humans etc., in order to cherish them by giving them the opportunity to see Me and to experience My pastimes and to converse with Me. I take birth also for the destruction of those who are hostile to such devotees and also for the restoration of the declining Vedic Dharma, which consists of devotion to Me. The main purpose of the incarnation is to reveal the adorable [divine] form in order to foster devotion. The destruction of the wicked is the secondary purpose only. There is no specific restrictions of Yugas like Kṛta, Treta etc., for the appearance of Divine Incarnations.