Danaë was the daughter of King Acrisius of Argos, whom an oracle had prophesied that he would be killed by his daughter’s son. To keep her childless, he locked her into a tower, but Zeus impregnated her in the shape of golden rain. The child was Perseus. Acrisius cast mother and son out to see in a wooden box, but they were saved and of course in the end the prophecy was fulfilled.
As early as Horace and Terence, authors have used the story as a metaphor for the power of gold, and most paintings of Danaë are thinly veiled bordello scenes. But there is another interpretation, found most prominently in the Fulgentius metaforalis, which describes her situation as thus:
High up, walled in a tower, in great misery, surrounded by guards, pregnant, violated by gold she sits: chastity violated. Jan Gossaert (who signed as Joannes Malbodius from his place of birth, and is sometimes known as Jan Mabuse) seems to follow this interpretation in his 1527 painting, which is the oldest of this topic outside manuscripts. He not only emphasizes the tower situation most other artists ignore completely, he gives her a blue coat, the attribute of Mary.
Another remarkable thing about this painting is the similarity with the Danaë on a Boeotian red-figure crater from the classic era that the Louvre acquired in 1898. Jan Gossaert was the first Flemish painter to travel to Italy, maybe he saw a similar picture there. The Domus Aurea had already been discovered at the time, and the word grottesche had made its way into the Italian language.