In 1645 a priest from Qormi founded a Mission and endowed it with part of his property; through the years the Mission lost its initial fervour, but it was revived and given new life in 1811 by Rev. Philip Calleja of Qormi, who was resident in Żebbuġ. Encouraged by his friends, Rev. Bertu Attard of Żebbuġ and Rev. Ġan Nikol Camilleri of Siġġiewi, he decided to endow with his property the activity which he had initiated a few years before of visiting the countryside villages, preaching and hearing confessions. In 1813, during the plague epidemic, on his death bed he left all his possessions to the Mission. On the 15th July 1815 Bishop Ferdinand Mattei accepted the foundation of the PIA OPERA which is popularly known as the MISSJONI L-KBIRA.