In recent years scholars have focused greater attention on the potential benefits of applying Bayes’ Theorem to arguments in biblical studies. Scholars such as Christoph Heilig and Laura J. Hunt have, in different ways, appealed to Bayes’ Theorem—a fundamental formula used in statistics—in their research, while a small but engaged community has sprung up online to explore the connection. Still others have begun to look at the potential of applying Bayes to textual criticism. The purpose of this paper is to explore—and ultimately commend—the practice of appealing to Bayes’ Theorem for biblical studies arguments by looking at a test case: the possible use of the narrative arc, or plotline, of Samuel-Kings as a major structural feature in Luke-Acts. This paper will present the basic contours of Bayes’ Theorem, focusing especially on the all-important distinction between prior probability and conditional probability. It will then present the test case as a Bayesian argument, laying out various factors of both background and conditional probability that might be taken into account for an overall probability judgment concerning the thesis. The paper will aim to demonstrate that, while using Bayes cannot guarantee anything approaching epistemological certainty, it can nevertheless be a useful tool to sharpen arguments and to compare competing proposals on particular biblical-theological topics.