There seems little reason for a philosopher to have religious faith. Beliefs derived from faith are often described as being without evidence or sacrosanct from scrutiny. This is not the belief of St. Thomas Aquinas. I begin the paper by drawing necessary distinctions to other forms of intellectual assent to make clear exactly what Aquinas means when he writes of fides. I then seek to explain how Aquinas seeks to ground the preambles in faith in his philosophical investigations of God, and how the gap between what is known by philosophy and what is known by theology allows for the necessary elements of voluntary actions that make faith virtuous while at the same time keeping it an authoritative epistemic tool. I end the paper by addressing ...