idaṁ te nātapaskāya nābhaktāya kadācana
idaṁ te nātapaskāya nābhaktāya kadācana |
na cāśuśrūṣave vācyaṁ na ca māṁ yo’bhyasūyati ||
(Śrīmad Bhagavad-gītā: 18.67)
“[Bhagavān Śrī Kṛṣṇa:] Neither to someone who is neglectful of austerity, nor to a non-bhakta, nor to someone who does not wish to listen, nor to someone who casts aspersions on me is this [i.e., this śāstra, Śrīmad Bhagavad-gītā] ever to be spoken.”