MEN AND ANGELS by Theodora Ward. 241 pages. Viking. $7.50.
Even the entirely godlessprovided they are not entirely artlessknow that Christmas began with an angel. The soaring radiance of medieval and Renaissance art turned again and again to the Annunciation and the astonishing moment when Gabriel first appeared to Mary with the slightly scandalous news that she was about to become the mother of Christ. Multiplied and modified by commerce, these and kindred images of angels flying, angels tootling on long trumpets, angels simply adoring have become as much a part of worldly Christmas...