The audacity of Christian art: Putting God in His place: Here, everywhere, and nowhere | National Gallery

Christians believe that God is eternal and omnipresent. Christ, who is God the Son, came down from heaven, lived on earth for a particular time and in specific places, died, was resurrected and ascended again to heaven. In this episode I'll be looking at how artists use place to explore the relationship between God (as God is everywhere and nowhere always and beyond time) and the particularity of Christ's presence in the here-and-now of historical time. We're going back to the Conservation department to look at a wonderful example of this use of presence and place in a picture by the 15th century Florentine painter, Lorenzo di Credi. It appears to show a beautiful, fashionable, woman breastfeeding her baby. This deliciously chubby baby with his dimpled flesh and his mother's golden hair and rosy cheeks, is very, very human. It would be easy to forget that he isn't only human. But I think there's something curious about the place in which they are set. At first glance the architecture appears unremarkable. But many people find that when they look again, the pillars seem to jump out of alignment. The one on the left suddenly seems to be set deeper into the distance and the one on the right to jump forwards. The building becomes confusing. We don't know whether Lorenzo di Credi meant to create a mystery - quite probably not - but the effect of these pillars is unsettling and the more we look at them the more mysterious it seems. Perhaps we can think of the building as a metaphor for the Virgin and Child. These figures who look like a beautiful, fashionable young woman and her baby, are in fact the sinless Mother of God and Christ Incarnate. Creating a mysterious location for them encourages us to look and think more carefully. It pushes us away from imagining that we have made sense of everything in the image. As artists from the Renaissance onwards were able to depict an increasingly realistic impression of depth and space, they encountered a problem. The more the space in a painting looks like 'real' space with real figures in it, the harder it is to show that this space is sacred. The more challenging it is to show Christ's divinity. One way of resolving this problem is to incorporate an element of the 'unreal' into the painting. By creating an implausible building, for instance, the artist can draw our attention to the paradoxical nature of his greater task of painting Christ. Of course, the mystery of the Incarnation begins - at least in an earthly sense - with the Annunciation: the moment when the Angel Gabriel announces to the Virgin Mary that she will conceive and give birth to the Son of God. If painting Christ as human and divine is difficult, how does an artist convey what is happening at the moment of Christ's conception when we can't see him at all? One of the most powerful responses to this problem has been to respect the invisibility of the event: to show us that we cannot see it. In many Annunciations we see the angel on the left, the Virgin on the right, and a space between them. In this version by Filippo Lippi, we see the Virgin in an enclosed garden; a metaphor for her purity. She is protected from ordinary, physical penetration. Separated even from the angel. There's no physical contact. The horizontal plane tells us that the Virgin is chaste and set apart and we can follow the angel's message on this horizontal axis as it travels from the angel on the left, across that central space, to the Virgin on the right. The vertical axis, on the other hand, tells us that the Virgin is connected to God. Light is descending from the hand of God at the top of the painting, flowing with the dove who symbolises the Holy Spirit, down to the Virgin on the right. Divine light is descending. God is incarnating. But as well as the horizontal and vertical axes which tell us the story, we're also looking into the perspective of the picture on an axis which runs from our viewing point, to the vanishing point in the infinite distance. And as we look towards the infinite, towards the divine, our gaze intersects with the message of the angel. Lippi can't show us the mystery of Christ's conception, but he gives us a spatial metaphor for it: he uses place. And to make this mystery even clearer, or even more mysterious, the vanishing point - that point of infinity, is blocked. We can't see that far. There's a stone wall in the way. At the point when we're looking most deeply into the image, we are returned to the surface. You can see this spacial device time and again in paintings of the Annunciation. It's as if the very structure of the image, its own architecture, tells us that we can only understand so much of what is happening here, and it brings us up short.