A Persian seet (generally rich merchants), distinguished by their beards and dress. When one of them dies, a cock is driven out of the poultry yard; if a fox seizes it, it is a proof that the soul of the deceased is saved. If this experiment does not answer, they prop the dead body against a wall, and if the birds peck out the right eye first, the Keber is gone to heaven; if the left eye, the carcase is flung into the ditch, for the Keber was a reprobate.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Keber' from Infoplease: