Ra was the sun god who protected the world from armies of the chaos serpent Apep. Ra was also the first pharaoh. Isis was the goddess of Magic, and Osiris' wife. To get Osiris on the throne she had a poisonous snake bite Ra's leg. Ra knew that Isis could heal him, so she made him give her his secret name. If a person had your secret name then they could control you. Since Isis knew Ra's secret name she convinced him to retire from being pharaoh leaving Osiris to take the throne.