Apap (Eg.), in Greek Apophis. The symbolical Serpent of Evil. The Solar Boat and the Sun are the great Slayers of Apap in the Book of the Dead. It is Typhon, who having killed Osiris, incarnates in Apap, seeking to kill Horus. Like Taoer (or Ta-ap-oer) the female aspect of Typhon, Apap is called “the devourer of the Souls”, and truly, since Apap symbolizes the animal body, as matter left soulless and to itself. Osiris, being, like all the other Solar gods, a type of the Higher Ego (Christos), Horus (his son) is the lower Manas or the personal Ego. On many a monument one can see Horus, helped by a number of dog-headed gods armed with crosses and spears, killing Apap. Says an Orientalist : “The God Horus standing as conqueror upon the Serpent of Evil, may be considered as the earliest form of our well-known group of St. George (who is Michael) and the Dragon, or holiness trampling down sin.” Draconianism did not die with the ancient religions, but has passed bodily into the latest Christian form of the worship.
Source: H.P.Blavatsky - The Theosophical Glossary