[A theophany, though a harbinger of the incarnation, differs from it, by not effecting a hypostatical or personal union between God and the creature. When the Holy Spirit appeared in the form of a dove, he did not unite himself with it. The dove did not constitute an integral part of the divine person who employed it. Nor did the illuminated vapor in the theophany of the Shekinah. But when the Logos appeared in the form of a man, he united himself with it, so that it became a constituent part of his person. A theophany, as Augustin notices, is temporary and transient. The incarnation is perpetual.—W.G.T.S.]