Achilles

c. 1300, aue, "fear, terror, great reverence," earlier aghe, c. 1200, from a Scandinavian source, such as Old Norse agi "fright;" from Proto-Germanic *agiz- (source also of Old English ege "fear," Old High German agiso "fright, terror," Gothic agis "fear, anguish"), from PIE *agh-es- (source also of Greek akhos "pain, grief"), from root *agh- (1) "to be depressed, be afraid" (see ail).

The current sense of "dread mixed with admiration or veneration" is due to biblical use with reference to the Supreme Being. To stand in awe (early 15c.) originally was simply to stand awe.

Al engelond of him stod awe.

["The Lay of Havelok the Dane," c. 1300]

Awe-inspiring is recorded from 1814. 

"uneducated, non-professional; non-clerical," early 14c., from Old French lai "secular, not of the clergy" (12c., Modern French laïque), from Late Latin laicus, from Greek laikos "of the people," from laos "(the common) folk, the people, the crowd; the military; a tribe," in the New Testament especially "the Jewish people," also "the laity," a word of unknown origin. Beekes writes that it is "most often connected with" Hittite lahh- "campaign" and Old Irish laech "warrior," but that the form "is rather Pre-Greek, and has a Pre-Greek suffix -it(o)-. In Middle English, contrasted with learned, a sense revived 1810 in contrast to expert. Laic is a more modern borrowing directly from Late Latin.