The Descent of the Holy Spirit on the Blessed Virgin and the Apostles is currently the altarpiece found over the side altar, replacing the original, which can be found in the main sacristy. The artist behind this masterpiece is Francesco Grandi (1831-1891), who also painted its two adjacent lunettes. This artwork is thought to be an attempt at fitting in with the Baroque style found throughout the Cathedral. A second altar piece, this time from Pietro Gagliardi (1809-1890), depicting Maria Melitae Patrona may also be found over the second chapel. Along with this piece, which depicts Our Lady looking over the Grand Harbour and Marsamxett Harbour, Gagliardi also painted two lunettes which represent the Crowning of the Blessed Virgin, and the Assumption in Heaven. The coat-of-arms of the Maltese Castelletti Family may be found flanking the altar.
The North Aisle
A remembrance to the Bishop Publio Sant may be found in the chapel in the form of a statue created in Rome by Mario Gori in 1874. Opposite to this, a bronze monument of Archbishop Michael Gonzi (1944-1976), who was the first Metropolitan Archbishop of Malta, may be found. This statue was created by the Maltese sculptor Vincent Apap in 1971. Salvaged from the ruins of the old cathedral after the 1693 earthquake, the chestnut timber door in the next aisle was adapted in order to fit the door of the old sacristy found within the new building. Cola Curmi and Joanni Calleya had created this door back in 1535, with the ironwork possibly being that of Pietro Blondel. The woodwork on the door is of a Sicilian inspiration. The statues of Apostles Peter and Paul crown the door, flanked by the shields of the municipality of Mdina as well as the vacant bishop.