BG 13.11-13
Unflinching devotion to Me by yoga, without other objects, resort to sequestered places, absence of enjoyment in the company of men, Constancy in the wisdom of the Self, understanding of the object of essential wisdom; that is declared to be the Wisdom; all against it is ignorance. I will declare that which ought to be known, that which being known immortality is enjoyed—the beginningless supreme Eternal, called neither being nor non-being.