The directive is not merely implied by the choice of site or the quality of the stonework, but written out in plain Latin, circling the slab along its two sides, its ends, and partway up the shaft of the carved cross at its centre. It is an unusual act of territorial assertion from the grave.

The slab measures 1.83 metres long and just under 60 centimetres wide, with a crack running across its lower end. Its surface carries a seven-armed segmental cross worked in relief, with fleur-de-lis terminals and a motif of three cross-bands at the junction of the head and shaft, the whole cross set on an elaborate pillar-base form. The inscription is cut in Black Letter, the angular gothic script common to formal documents and monumental carving of the late medieval period, and records that it marks Edward, son of Thomas Butler, who died on the 23rd of September 1503. It was his wife, Margaret Comyn, who commissioned the tomb. The Latin closes with a request that passers-by say a Pater and an Ave for their souls, the standard intercessory formula of the period. The prohibition against outside burial, framed with the word "alienus", meaning a stranger or outsider, suggests the Butlers and Comyns were claiming not just a grave plot but a kind of perpetual ownership of a particularly prestigious space within one of Ireland's most significant ecclesiastical complexes. Whether the instruction was ever tested is not recorded.