ABSTRACT
This chapter asserts that the motif of Saint Ambrose standing in an archway was popular in medieval Milan because it referred to the eternal protection of the local patron saint. Further, the motif of the gate signified Saint Ambrose's Early Christian spatial theology of the progression of the soul from profane to sacred, which the archbishop promoted in his writings, his liturgy, and his ecclesiastical building program in Milan. To gain a better sense of Ambrose's spatial theology, this chapter roughly reconstructs the Early Christian viewer's experience of the gateway motif at the Basilica Martyrum, the church Ambrose had arranged to serve as his mausoleum. Through a series of progressive stational thresholds the believer moved from the profane space outside the basilica toward the most holy space of the altar. At each threshold, the viewer experienced a spiritual transformation toward greater sanctification, resolving with a momentary spiritual ascent to heaven at the altar-threshold under which Ambrose's relics were buried. Ambrose's physical remains provided the link between heaven and earth, a link that was liturgically activated by the contemporary archbishop during the Eucharist. Medieval portrayals of Ambrose in an archway therefore illustrated his episcopal role as intercessor at the porta coeli (figure 1.1).
