Among the Jews, as among most Oriental peoples, the beard was especially cherished as a symbol of virility; to cut off another man's beard was an outrage (II Kings, x, 4); to shave or to pluck one's own beard was a sign of mourning (Jer., xli, 5; xlviii, 37); to allow the beard to be defiled constituted a presumption of madness (I Kings, xxi, 13). Certain ceremonial cuttings of the beard which probably imitated pagan superstition were strictly forbidden (Lev., xiv, 9). These usages which we learn from the Bible are confirmed by the testimony of monuments, both Egyptian and Assyrian, in which the Jews are invariably depicted as bearded. The Egyptians themselves commonly shaved, and we are told that Joseph, on being taken from his prison, was made to shave before appearing in the presence of the king (Gen., xli, 14).  (text taken from http://www.newadvent.org/cathen/02362a.htm)