The arch and the window above it appear to date from the 15th century, centuries older than the building that now frames them. The church itself replaced an 18th-century T-plan chapel, a common form for rural Catholic worship in the penal and post-penal periods, which itself stood on a site with no known ecclesiastical history before 1700. The medieval stonework, in other words, arrived here from somewhere else.

The most likely source is the ruined medieval church at Castlelost, roughly three kilometres to the north-east. The connection is more than geographical. The doorway at Meedian is built in two orders, meaning it has two concentric layers of arched stonework, with mouldings of hollows and rolls and no capitals on the jambs. Carved into the left side of the arch is a star symbol, which reappears beneath the hood moulding of the window directly above the entrance. Lower down, the jambs carry their own ornament: a stylised plant motif on the left stone and a two-strand interlace pattern with triangular terminals on the right. That interlace carving closely resembles the decorated panels on the east window at Castlelost, where the upper section of the medieval doorway is now missing. The implication is fairly direct: what Castlelost lost, Meedian may have gained. Salvaged stonework being incorporated into later buildings was common practice, and the carved detail here is consistent with late medieval Irish ecclesiastical masonry of the kind found across the midlands.

A 3D model of the doorway is available online at skfb.ly/oJAJL, which gives a useful sense of the carving's depth and detail, particularly the interlace work, before or after visiting the site in person.