While there is agreement among many (but not all) theologians and philosophers that a miraculous event should be conceived in opposition to the natural order, there is disagreement about why this opposition must be present. In this paper I propose to examine Antony Flew's explanation of how and why miracles and nature are opposed, suggesting that his account is, as it stands, problematical and in need of revision. In evaluating Flew's position I shall focus on comments he makes when discussing Hume's account of miracles, and while I shall not attempt to argue the correctness or incorrectness of Flew's interpretation of Hume, I think that what I say, if correct, bears importantly on that issue.