Love Among the Ruins by Warwick Deeping

Fra Balthasar rubbed his colours in the chapel of Castle Avalon, and stared complacently upon the frescoes his fingers had called into being.

A migratory friar, Fra Balthasar had come from the rich skies, the purple vineyards, the glimmering orange groves of the far south. Gossip hinted that a certain romantic indiscretion had driven him northwards over the sea. A "bend sinister" ran athwart his reputation as a priest. Men muttered that he was an infidel, a blasphemous vagabond, versed in all the damnable heresies of antiquity. Be that as it may, Fra Balthasar had come to Gilderoy on a white mule, with two servants at his back, an apt tongue to serve him, and much craft as a painter and goldsmith. He had set up a _bottega_ at Gilderoy, and had cozened the patronage of the magnates and the merchants. Moreover, he had netted the favour of the Lord Flavian of Avalon, and was blazoning his chapel for him with the lavish fancy of a Florentine.