A man bound by the hands and feet cannot free himself—he must be helped by a person who is unbound. Because the bound cannot help the bound, the rescuer must be liberated. Therefore, only Lord Kṛṣṇa, or His bona fide representative the spiritual master, can release the conditioned soul. Without such superior help, one cannot be freed from the bondage of material nature.
Śrīla Prabhupāda's room Conversation with Mr. & Mrs. Wax, Writer and Editing Manager of Playboy Magazine -- July 5, 1975, Chicago
