Which Christian beliefs did Thomas Aquinas believe depended on divine revelation rather than reason alone?

For Thomas Aquinas, theology is a science derived from propositions accepted as certain because they are revealed by God, whereas philosophy relies solely on the natural light of reason. While Aquinas believed human reason could provide definitive proofs for the existence of an infinite being (the Five Ways), he maintained that positive knowledge of the divine nature was limited without revelation.12

Aquinas held that certain truths—specifically those concerning the inner nature of God—could not be fully grasped through natural reason alone. For instance, he noted that apart from revelation, one could only describe God through analogy or by stating what God is not (apophatic theology). Furthermore, while he argued that the immortality of the soul could be demonstrated rationally, he viewed the ultimate end of human beings—the beatific vision of God—as a supernatural reality that elevates human nature beyond its natural abilities. In his methodology, reason operates within the framework of faith to elaborate on these revealed mysteries, integrating rational structures into the light of divine truth.231