To the ancient Greeks, Asclepius was the god of medicine.
Son of Apollo, in life he devoted himself to caring for the sick to alleviate human suffering; some legends even tell that he managed to revive the dead.
Because he had dared to defy the natural law that all humans are mortal, Zeus flew into a rage and killed him with his thunderbolt.
From that moment on, Asclepius was revered as a god by all ancient Greeks and later by the Romans.