In the wake of Karl Rahner, a range of theologians have made a compelling case that theology cannot afford to dismiss popular fascination with “the End-times,” nor downplay the apocalyptic tenor of the New Testament itself. Nevertheless in Catholic theology apocalypticism remains something of an oddity, a message in search of a credible form. This essay explores the apocalyptic tenor of Thomas Merton's mature period (1957–68) in order to propose some crucial distinctions between apocalyptic in an authentically “Catholic,” “analogical,” or “ironic” mode, and other, more dialectical forms of apocalyptic that have long dominated American religious and popular consciousness. Bringing Merton into dialogue with Russian sophiology, William Lynch, Johannes Baptist Metz, and others, the author highlights Merton's contribution to the difficult question of form: that is, how apocalypticism might be communicated in a way that seizes on the historical urgency of the gospel but also refuses to cede to a mythological, dialectical, or dangerously idolatrous imagination.