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Bhagavad-gita As It Is
BG Chapters 7 - 12
BG 7.3, Purport:
Even the great demigods are sometimes confused about Kṛṣṇa (muhyanti yat sūrayaḥ). Māṁ tu veda na kaścana: "No one knows Me as I am," the Lord says. And if one does know Him, then sa mahātmā su-durlabhaḥ. "Such a great soul is very rare."