In this paper I argue that Aquinas’ account of analogy provides resources for resolving the prima facie conflict between his claims that (1) the divine relations constituting the persons are “one and the same” with the divine essence; (2) the divine persons are really distinct, (3) the divine essence is absolutely simple. Specifically, I argue that Aquinas adopts an analogical understanding of the concepts of being and unity, and that these concepts are implicit in his formulation of claims about substance (...) and relation in the Trinity. I then show how Aquinas appeals to key structural features of analogical concepts, notably, the simpliciter/secundum quid characterization, to resolve apparent conflicts between the unity of substance and distinction of relations in the Trinity. (shrink)