The eagle is an attribute of St John the Evangelist and one of the four beasts from the Book of Revelation.

It is also an attribute of Jupiter (or Zeus). According to Ovid's 'Metamorphoses' Jupiter disguised himself as an eagle in order to carry off the youth, Ganymede, with whom he had fallen in love.

Damiano Mazza
about 1575
Attributed to Damiano Mazza: 'The Rape of Ganymede'