To heighten the effect of rigging the work’s perspective, Angelico has gone further still to situate the fresco’s vanishing point to a spot that lies tantalisingly just beyond the bars of a small window in the back of the painting. As one climbs the stairs towards Angelico’s Annunciation, in other words, their eyes are simultaneously lured into and barred from entering this semi-permeable boundary that separates the world we can see from one that lies just outside it. By establishing an exit for our eyes and at the same time frustrating our access to it, Angelico has subtly raised the stakes on looking. The predicament of his painting, which compels us to pass through its world while forcing us to remain in it, is one to which any soul can relate.
Angelico’s contemporaries would have instantly recognised his employment of the barred window, beyond which lies a secret and unreachable garden, as a version of the hortus conclusus – a recurring symbol in Christian art and literature of the era. Meaning “enclosed garden”, the hortus conclusus was a complex metaphorical device that recalled, on the one hand, the loss of paradise, and, on the other hand, the Mary’s own immaculateness. To educated Medieval eyes, the window’s bars symbolised the Virgin’s own inviolable purity. To impel us towards that obstructed aperture, Angelico was dabbling in religiously risky and audacious choreography – luring us to contemplate, however subliminally, a penetration of the impenetrable.
Remove that escape route from the work, and the impact of Angelico’s fresco would be infinitely diminished. The barred window, which hovers in the sightline of the fresco’s two protagonists (further amplifying its importance), creates an invigorating tension in the work. Remove it from the blueprint of his fresco, shutter it completely, or draw heavy drapes across it, and the painting closes down. Its optical magic collapses. Angelico has meticulously measured just how much a glimpse of paradise we need to keep going. And nothing more.
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