The church associated with Cyfelach, reflecting the place-name and Cyfelach is the dedication given by Browne Willis (Gaffeliak). Nonetheless, Browne Willis gives the feast day of the parish as 1 March, St David's Day, and the relationship with David goes back to Rhigyfarch's Vita Sancti David, in which David founds a monastery here.

It seems likely that David's cult was established here by, or soon after, the Life was written: Wade Evans typically interprets this as David supplanting the original dedication to the saint found in the place-name. The dedication of the church is currently shared by both saints.