Piehler

Allegory
In ordinary usage, allegory is "when the events of a narrative obviously and continuously point to another simultaneous structure of events or ideas, whether historical events, moral or philosophical ideas, or natural phenomena" (PEPP). Perhaps the finest example of allegory in its purest form is the medieval play Everyman.

For Barfield, allegory should be understood as "a natural development from myth rather than its enemy" (Barfield is paraphrasing Paul Piehler's The Visionary Landscape [RM 94]). "viewed historically," he argues, "allegory was figurative by inheritance from a pre-rational mode of perception" (RM 105). But "Is it not clear," Barfield asks, "that we find allegory desiccated precisely because, for us, mere words are themselves desiccated--or rather because, for us, words are 'mere'?" (SA 86).

Barfield hypothesizes that we might well experience a 'rediscovery of allegory" with the coming of final participation and the advent of a new, less literal conception of language.
 

See in particular "The Rediscovery of Allegory," Parts I and II (RM 93-100, 101-110).