The painter of this work was a collaborator of the sculptor Gil de Siloe and was familiar with Northern art. John the Baptist, recognisable by his clothing and by the lamb on the book, has been painted with great care. The use of strong light to emphasise his bulk is influenced by Van Eyck. On a smaller scale, on the right, is the donor, a cistercian nun. The painting probably comes from a Cistercian convent in Valladolid.