In Greek and Roman mythology, the Palladium or Palladion was a cult image of great antiquity on which the safety of Troy and later Rome was said to depend, the wooden statue (xoanon) of Pallas Athena that Odysseus and Diomedes stole from the citadel of Troy and which was later taken to the future site of Rome by Aeneas. The Roman story is related in Virgil's Aeneid and other works. Rome possessed an object regarded as the actual Palladium for several centuries; it was in the care of the Vestal Virgins for nearly all this time.

In the practice of religion, a cult image is a human-made object that is venerated or worshipped for the deity, spirit or daemon that it embodies or represents. In several traditions, including the ancient religions of Egypt, Greece and Rome, and modern Hinduism, cult images in a temple may undergo a daily routine of being washed, dressed, and having food left for them. Processions outside the temple on special feast days are often a feature. Religious images cover a wider range of all types of images made with a religious purpose, subject, or connection. In many contexts "cult image" specifically means the most important image in a temple, kept in an inner space, as opposed to what may be many other images decorating the temple.