The Rod of Asclepius, also known as the Asklepian, is an ancient symbol associated with astrology, the Greek god Asclepius, and with medicine and healing. The Asklepian is not to be confused with the caduceus; the staff carried by Hermes in Greek mythology. The same staff was also borne by heralds in general, for example by Iris, the messenger of Hera. It is a short staff entwined by two serpents instead of one and sometimes surmounted by wings. In Roman iconography it was often depicted being carried in the left hand of Mercury, the messenger of the gods, guide of the dead and protector of merchants, shepherds, gamblers, liars and thieves.The Asklepian sign consists of a serpent entwined around a staff. The name of the symbol derives from its early and widespread association with Asclepius, the son of Apollo, who was a practitioner of medicine in ancient Greek mythology. His attributes, the snake and the staff, sometimes depicted separately in antiquity, are combined in this symbol. Hippocrates himself was a worshipper of Asclepius.
The significance of the classical serpent has been interpreted in many ways; sometimes the shedding of skin and renewal is emphasized as symbolizing rejuvenation, while other assessments centre on the serpent as a symbol that unites and expresses the dual nature of the work of the physician, who deals with life and death, sickness and health. The ambiguity of the serpent as a symbol, and the contradictions it is thought to represent, reflect the ambiguity of the use of drugs, which can help or harm, as reflected in the meaning of the term pharmakon, which meant drug, medicine and poison in ancient Greek. Products deriving from the bodies of snakes were known to have medicinal properties in ancient times, and in ancient Greece, at least some were aware that snake venom that might be fatal if it entered the bloodstream could often be imbibed. Snake venom appears to have been prescribed in some cases as a form of therapy.However, the serpent may have its origin in the Bible. The so-called Nehushtan, in the Hebrew Bible, was a sacred object in the form of a snake of brass upon a pole. The priestly source of the Torah says that Moses used a ‘fiery serpent’ to cure the Israelites from snakebites. It is mentioned in Numbers 21:4-9:4 And they journeyed from mount Hor by the way of the Red sea, to compass the land of Edom: and the soul of the people was much discouraged because of the way. 5 And the people spake against God, and against Moses, Wherefore have ye brought us up out of Egypt to die in the wilderness? for there is no bread, neither is there any water; and our soul loatheth this light bread. 6 And the LORD sent fiery serpents among the people, and they bit the people; and much people of Israel died. 7 Therefore the people came to Moses, and said, We have sinned, for we have spoken against the LORD, and against thee; pray unto the LORD, that he take away the serpents from us. And Moses prayed for the people. 8 And the LORD said unto Moses, Make thee a fiery serpent, and set it upon a pole: and it shall come to pass, that every one that is bitten, when he looketh upon it, shall live. 9 And Moses made a serpent of brass, and put it upon a pole, and it came to pass, that if a serpent had bitten any man, when he beheld the serpent of brass, he lived.Coincidentally, on another subject: the Asklepian looks like a direct representation of ancient traditional treatment of Dracunculus medinensis, the Guinea worm. The worm peeks out of disablingly painful ulcerous blisters to lay eggs, primarily when the wound is placed in water to cool and soothe it. The practitioner would pull the worm out slowly by winding it around a stick.