Time, according to medieval theologians and philosophers, was experienced in radically different ways by God and by his creation. Indeed, the obligation to dwell in time, and therefore to have no sure knowledge of what was to come, was seen as one of the primary qualities which marked the post-lapsarian state. When Adam and Eve were cast out of the garden of delights, they entered a world afflicted with the changing of the seasons, in which they were obliged to work and consume themselves with the needs of the present day and the still unknown dangers of the next. Medieval concerns about the use and abuse of time were not merely confined to anxiety about the present, or awareness of seized or missed opportunities in the past. The future was equally worrying, in particular the extent to which this part of time was set aside for God alone, or whether it was permissible to seek to know the future, either through revelation and prophecy, or through science. In the fourteenth and fifteenth centuries, the scientific claims of astrology to provide a means to explain the outcome of past and future events, circumventing God’s distant authority, became more and more insistent. This paper begins by examining one skirmish in this larger battle over the control of the future.