The patron of Marsico Nuovo is Saint Gianuario, celebrated on 26 August: today he is the principal patron of the archdiocese.
His body was found in the church of Santo Stefano — today's church of San Gianuario — destroyed by the earthquake, and was brought into the co-cathedral in 1827, when the rebuilding ordered by Bishop Ignazio Marolda was completed; along with the remains, the statue by Giacomo Colombo was moved too. On 27 August 1899 Bishop Durante dedicated the co-cathedral under the title of Saint Gianuario bishop and martyr. The town's second feast, regarded as patronal in pectore, is that of the Madonna del Carmelo, on the last Sunday of July.
