Often understanding the possibilities for health and human flourishing also entails understanding our human limits. Among the many contemporary approaches to the character and goals of medicine, the work of Daniel Callahan is especially sustained and significant. Through an abundance of books, essays, and lectures spanning forty years, he has addressed, often controversially, medicine’s limits, its relation to the “research/technological imperative,” care for the aging, and, finally, the nature and meaning of death itself. I wish to take part in this conversation by way of attention to Karl Barth’s theology of aging and death. Barth’s dialectical account of death as both evil and good, curse and calling, coincides with Callahan’s analysis in a number of ways. More importantly, it prompts fruitful reflection on not only the normative status of human mortality and finitude, but also the definitions, boundaries, and goals informing medical practice. Given his view of death and our allotted time as “calling,” aging plays a special role in the Christian community and prepares us for accepting those final limits in what it means to be human. Thus, by better understanding our finitude and the importance of end-of-life care, we better understand what it means to flourish with gratitude, humility, and faithfulness before God. Following an explication of Callahan’s position on the nature and meaning of death for medicine, I subsequently articulate Barth’s view of aging and death as part of our calling. In a concluding section, I critically consider the contributions of both authors for a more truthful theological appraisal of mortality and finitude as these limits help circumscribe the goals of medicine in relation to health and human flourishing.