This realization (of Krsna as the Supreme cause) is possible only for devotees who have fully surrendered unto the lotus feet of the Lord; for others it is not possible. This is confirmed by the Lord Himself in Bhagavad-gita: Revision history
Diff selection: Mark the radio buttons of the revisions to compare and hit enter or the button at the bottom.
Legend: (cur) = difference with latest revision, (prev) = difference with preceding revision, m = minor edit.