SECRETA ALCHEMIAE MAGNALIA, a work attributed to St. Thomas Aquinas, illuminates an oft-overlooked facet of the illustrious theologian - his contributions to alchemy. Living in the 13th century, a time brimming with burgeoning interest in natural philosophy, Aquinas was intrigued by alchemical pursuits, primarily seen through his theological and philosophical perspectives. In the manifold depths of his influential works, Aquinas frequently engages with alchemical principles, pondering over transformative properties of substances - a critical pillar of alchemical studies. Yet, his inquiry always gravitates towards the metaphysical and spiritual implications of these transformations. Aquinas's goal was not to transmute base metals into gold but to comprehend the divine principles that govern such changes. SECRETA ALCHEMIAE MAGNALIA provides an invaluable testament to Aquinas's profound intellectual versatility. His exploration of alchemical concepts integrates seamlessly with his broader theological discourse, shedding light on a dimension of his thought that has often remained shrouded in obscurity.