My favourite painting: Timothy Mowl

Professor Timothy Mowl on the Brera Altarpiece by Piero della Francesca

"My son introduced me to this wonderful painting, so it has a shared resonance. I was drawn to its meticulously correct depiction of Classical architecture, the spiritual serenity of the assembled cast, many obviously drawn from life, as if posing for a christening photograph, and, in stark contrast, the armour-suited donor, Federico da Montefeltro, humanist and bruiser, who lost the bridge of his nose and an eye in a tournament – this is his best side.

"But the most extraordinary element is the suggestively shaped shell hood and dangling ostrich egg denoting female fecundity. The Early Renaissance at its most captivating."

Timothy Mowl is an architectural and landscape historian, who has published more than 30 books.

Charlotte Mullins comments on the Brera Altarpiece

In a light-filled classical atrium, the Virgin Mary sits on a dais as the baby Jesus sleeps in her lap. She is surrounded by saints and archangels, as a kneeling man in the armour of a military commander prays before her. We see him in profile and his distinctive nose and curly black hair mark him out as Federico da Montefeltro, the powerful Duke of Urbino, aged about 50.

Now known as the Brera Altarpiece, this sacra conversazione was commissioned by the Duke to mark the birth of his son and heir, Guidobaldo, and was originally displayed in the Church of San Bernardino in Urbino. It was painted by Piero della Francesca, a Renaissance artist who had trained in Florence and who spent many years at the Duke’s court.

In the painting, the figures are serious and still, as if carved from stone. It is the lofty architecture that draws our eye. Della Francesca had studied the new science of perspective and all his understanding comes to the fore here. Look at the barrel vault receding behind the Virgin — it is as if she is sitting in her own ornate wing of the church.

The ostrich egg hanging in the air in front of the scallop-shell ceiling is one of the great mysteries of Renaissance art — the ostrich was a symbol of the Montefeltro family, but the egg could also symbolise the Virgin birth or represent the plumb line of geometrical perspective.

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