Srimad-Bhagavatam: Canto 3 - Chapter 1 - Verse 5
मैत्रेय उवाचसाधु वीर त्वया पृष्टमवतारकथां हरे: ।यत्त्वं पृच्छसि मर्त्यानां मृत्युपाशविशातनीम् ॥ ५ ॥
maitreya uvācasādhu vīra tvayā pṛṣṭamavatāra-kathāṁ hareḥyat tvaṁ pṛcchasi martyānāṁmṛtyu-pāśa-viśātanīm
The great sage Maitreya said: O warrior, the inquiry made by you is just befitting a devotee because it concerns the incarnation of the Personality of Godhead. He is the source of liberation from the chain of birth and death for all those who are otherwise destined to die.
The great sage Maitreya addressed Vidura as a warrior not only because Vidura belonged to the Kuru family but because he was anxious to hear about the chivalrous activities of the Lord in His incarnations of Varāha and Nṛsiṁha. Because the inquiries concerned the Lord, they were perfectly befitting a devotee. A devotee has no taste for hearing anything mundane. There are many topics of mundane warfare, but a devotee is not inclined to hear them. The topics of the warfare in which the Lord engages do not concern the war of death but the war against the chain of māyā which obliges one to accept repeated birth and death. In other words, one who takes delight in hearing the war topics of the Lord is relieved from the chains of birth and death. Foolish people are suspicious of Kṛṣṇa’s taking part in the Battle of Kurukṣetra, not knowing that His taking part insured liberation for all who were present on the battlefield. It is said by Bhīṣmadeva that all who were present on the Battlefield of Kurukṣetra attained their original spiritual existences after death. Therefore, hearing the war topics of the Lord is as good as any other devotional service.