Medusa was originally a beautiful maiden. She worked in the service of the goddess Athena and was obliged to renounce lust. In this way she remained “pure” and was able to become a priestess in Athene’s temple.

She lived far in the north and guarded an entrance to Hades. But sadly you never got to see the sun there. Through frequent contact with the deceased, Medusa learned about the beauty and power of the sun and desperately wanted to see it. Athena refused her this.

Her beauty caught the attention of Poseidon, who desired her.

But Medusa made her way south without permission. There she met the sea god Poseidon and a passionate love affair ignited between the two. But of all things, the two chose a temple dedicated to Athena for their love affairs.

Athena was so angry that she turned Medusa into the creature she is known as — a monster most notorious for her writhing snake hair and stare. She had the body of a woman, teeth similar to boar's tusks and glowing eyes.

From the story of Perseus we learn that he was protected and guided in his endeavors to win the head of Medusa, primarily by Athena.

It was she who instructed him to act against Medusa in such a way that he would not see her face, but only its reflection in his shiny shield. This allowed Perseus to look at Medusa's head without having to look at him face to face. He cut off the head with the sickle that he had received as a gift from Athena, Hermes or Hephaestus.

The winged horse Pegasus leapt out of Medusa's neck. But the horse wasn't the only thing that came from her. With him was born, in the same way, the giant Chrysaor, the hero called “the one with the golden sword”.
From then on, Athena wore the mask-like head of Medusa either as a shield symbol or on her breastplate as special protection on her shield; later it became known as the Gorgoneion.