The present article seeks to show, with reference to Thomas Aquinas and Richard Swinburne, that classical theism cannot reconcile the idea of divine perfection with the modern idea of a person. It then proposes a solution which consists in applying to the doctrine of God the model of complementarity which Niels Bohr first used in quantum physics in his attempt to explain (among other things) the duality between wave and particle. This model is then applied by juxtaposing the description of God as a perfect being, established through the via negativa, and the description of God as a person, established through the via positiva as two contradictory, albeit necessary, descriptions.