The interior of the spaces of the presbytery area and the transept correspond to the volume, as designed by Roger’s original project. The difference between this part of the building and the other, consisting of the aisles, is the large triumphal arch, visible in its original height, on the transept side, and reduced by a sub-arch on the aisle side. The front of the transept leading into the apsidal spaces is characterised by the typical overlapping columns placed in angular niches. In the apsidal basin, the grandiose Christ Pantocrator, the King of Kings, emerges from the golden background. With his majestic embrace and stern but benevolent gaze, he welcomes the faithful while holding the Gospel firmly in his left hand. The volume has an open page, both in Greek and Latin, which contains the phrase from the Gospel of John: “I am the light of the world; Whoever follows me will never walk in darkness, but will have the light of life”.