इदं ते नातपस्काय नाभक्ताय कदाचन।
न चाशुश्रूषवे वाच्यं न च मां योऽभ्यसूयति।।18.67।।
।।18.67।।यह सर्वगुह्यतम वचन अतपस्वीको मत कहना अभक्तको कभी मत कहना जो सुनना नहीं चाहता? उसको मत कहना और जो मेरेमें दोषदृष्टि करता है? उससे भी मत कहना।
As this science of immortality is exceeding esoteric and confidential, Lord Krishna gives the mandate as to those whom Srimad Bhagavad-Gita should never be imparted to. 1) atapaskaya means one who does not exercise control of their senses 2) na abhaktaya means one who is not a devotee of Lord Krishna or any of His incarnations and expansions. A deeper interpretation is that it should never be given to one who has no love for Lord Krishna or any of His incarnation and expansions. Even if one is aspiring to receive initiation as a Vaisnava Brahmin; yet if one is devoid of loving devotion to Lord Krishna then the confidential teachings of Srimad Bhagavad-Gita should be restricted from them until qualified. 3) susrusave means one whos averse to submissive reverence to the spiritual guru 4) abhyasuyati means one who is envious and blasphemous to the Supreme Lord. To these four types of jivas or embodied beings Srimad Bhagavad-Gita should never be disclosed. For whatever they would hear about the Supreme Lords glories and potencies would make such vile miscreants offensive in their attitude and actions. The differences of case employed in the ablative form a-tapaskaya, a- bhaktaya etc. to the nominative form yo mam etc. is to emphasise the exceedingly despicable characteristics of those who are abhyasuyati who are just like poison vipers. The exposure of the wicked is more imperious then the laudation of the virtuous as the wicked are most degraded.