The name Portnascully is itself worth pausing on. In Irish, port can refer to a landing place, a bank, or a settlement, while the second element may derive from a personal name or a local term, giving the townland a faintly nautical or territorial quality that sits oddly in a landlocked county.

Beyond the fact of its existence and its classification as a church, the documentary record currently offers nothing further: no date of construction, no dedication, no named founder, no description of what survives above ground. County Kilkenny has a deep tradition of early medieval ecclesiastical settlement, with numerous small parish churches, monastic enclosures, and pre-Norman foundations scattered across its townlands, many of them reduced today to a gable end or a grassed-over outline in a field. Whether the church at Portnascully belongs to that early tradition or represents a later medieval foundation is, for now, an open question.