The Annunciation, c.1450/53 by Fra Filippo Lippi
Canvas Print - 23178-LFF

White lilies rise from a carved stone vase at the exact centre of the panel, splitting the composition into two worlds: the angel's garden on the left, Mary's chamber on the right. Fra Filippo Lippi lets that low wall do enormous work. It separates and connects, sacred visitor and mortal woman held apart yet clearly speaking to one another across the stems.

Gabriel kneels in profile, his peacock wings fanned into a dazzle of eyes and jewel-tones – teal, ochre, oxblood, gold. The feathers alone repay minutes of looking. Every barb seems individually considered, and one begins to understand why the Medici, who commissioned this pair of panels for their Florentine palace, loved such wings: the peacock was among their emblems, as was the diamond ring with two feathers carved discreetly into the wall beneath the lily vase. Wealth signals itself quietly here, threaded through devotion rather than announced.

Mary sits to the right, cloaked in that deep lapis blue Florentine painters reserved for her, over a rose-pink gown. Her head tilts down towards a small opening in the fabric at her waist, where a golden light glows – the moment of conception, made visible. Above her, God's hand emerges from a cobalt cloud, releasing the dove that streaks diagonally towards her body. It is one of the strangest and tenderest devices in Quattrocento painting: theology rendered as trajectory, an arrow of grace.

Look at the floor. The tiled perspective drives sharply back towards the shadowed doorway, and yet the room feels curiously shallow, as if Lippi were more interested in the surfaces – the embroidered gold coverlet on the bed, the damask draping her chair like a throne – than in convincing us of deep space. Perhaps that is the point. This is Mary as Queen of Heaven in a Medici interior, apricot-pink marble walls carved in the new classical taste, furniture that any wealthy Florentine would recognise from their own household.

The emotional register is hushed. No drama, no swoon. Gabriel's hand lifts in gentle address; Mary's crosses her breast in acceptance. One can almost feel the cool of the marble, the weight of stillness before speech resumes. Compared with Fra Angelico's more ceremonial Annunciations of the same decades, Lippi's version feels domestic, intimate, almost overheard.

Made around 1450 for a doorway inside the Palazzo Medici – possibly the study whose ceiling carried the zodiac – the lunette shape reminds us it was architecture as much as image. The Annunciation, after all, opened the Florentine year on 25 March. A painting to walk beneath, then, on the way into a room where time itself was mapped overhead. It still carries that threshold quality at the National Gallery in London today: a moment held between two states, forever about to change.