This chapter focuses on a single day during a late-sixteenth-century confrontation between Lutheran and Reformed theologians. As each side argued for its understanding of the meaning of infant baptism, each fastened on a different part of Martin Luther’s teaching. As the theologians argued, the distinction between the traditional understanding of sacramental baptism and something else, an “inward baptism,” became clear. Commitment to an inward baptism, which appeared to the Reformed to be a necessary consequence of Luther’s teaching, would eventually create space for evangelicalism.