The patron of San Daniele del Friuli is Saint Augustine, remembered on 28 August, while the town's holiday falls on 29 September, Saint Michael the Archangel: the cathedral and the parish are named after him, and the parish is also the seat of the Forania of San Daniele, twenty parishes of the archdiocese of Udine.
The church of San Michele is also tied to the thing the town is proudest of after its ham: in 1466 Guarnerio d'Artegna gave it 173 manuscript codices, and so the Biblioteca Guarneriana was born, one of the oldest public libraries in Italy. It holds illuminated works, a rare 14th-century edition of Dante's Inferno and the Levantine Bible, whose miniatures mix Western and Levantine manners.
