From his left shoulder springs a bird-like creature, possibly a peacock. The beard splits into two plaits at the jawline and may once have continued down the jamb as a roll-moulding curling into a spiral at the base. It is a surprisingly intimate piece of carving to encounter in what are now low, open ruins, the walls of the nave and chancel standing barely above head height.

The limestone church, built on a shallow projecting plinth, sits roughly ten metres west of the Augustinian Abbey on the island and is thought to date from the mid to late twelfth century, a dating suggested by the ground plan, the decorated stonework, and the style of the chancel arch. A Hiberno-Romanesque arch, that is, an arch blending Irish and continental Norman decorative conventions, originally divided the nave from the slightly elevated chancel, with three steps rising between them. The arch was largely destroyed and has been heavily reconstructed, surviving now only to the springers, the lowest stones from which the arch curves. The south jambstones retain a shallow roll-moulding with spiral terminations at the base, similar in style to the sidestone of a piscina, a small stone basin used for rinsing liturgical vessels, in the nearby abbey church; one stone from the north jamb is thought to have been removed and reused as that very sidestone. Above the masked capital, two chamfered stones decorated with bosses and Greek fretwork may be displaced string-course mouldings, their original position uncertain. A decorated stone on the south jamb carries a triangular fretwork pattern, possibly an impost moulding. The church is connected on its west side to a rectangular structure, inserted later, which formed the west range of the abbey complex.