The painting portrays not an event, but a dogma, or mandatory religious belief, of the Roman Catholic Church. According to church teachings, every human being since Adam and Eve is born with original sin, the consequence of Adam's eating the forbidden apple in the Garden of Eden. The doctrine of The Immaculate Conception states that Mary, the mother of Jesus Christ, alone among all humankind was conceived without original sin in the womb of her mother, Saint Anne.
This dramatic and exuberant composition conformed in both style and subject with the artistic principles ordained by the Catholic Church for Counter-Reformation art, which called for large-scale creations that evoke intense emotional response from the viewer. Light, color and movement are combined to create the illusion of a celestial vision. Installed on the main altar of the church, this towering altarpiece would have been the focal point of the visitor's experience. The heavens seem literally to open, revealing the Virgin Mary who, as the mediator of the heavenly and earthly realms, invites the viewer to participate in the mystical occurrence.