Within porch is C5 or C6 incised stone 'Rugniatio Livendoni' (the second word possibly an eroded Fili Vendoni) with two equal armed crosses one above the other, one encircled, probably added in C7 to C9. Possible Ogam marks on edge. Porch gives access to an earlier C19 whitewashed plastered passage with nave to right and former schoolroom now vestry to left. Stone flagged floor, six-panel door to left. Schoolroom and tower base not inspected: tower is said to have a stone with ring-cross incised over door and tall blocked tower arch. Schoolroom is said to have wood floor and flat ceiling, N wall blocked fireplace and a tablet of 1758. Double fielded-panelled 6-panel doors to nave. Fielded panels to corner cupboard. Nave has fine oak panelled roof in 12x25 small panels with moulded timbers. Green baize W door. N arcade to chapel of three bays, C15 octagonal piers and responds, with caps and bases, chamfered pointed arches. The N respond may be earlier. No chancel arch, one step to chancel, one step after chancel stalls, one step to sanctuary. Victorian encaustic tiles. NE chapel has similar roof of 10 x 18 panels. Two steps.
Font: possibly C11, small bowl with band of raised crude quatrefoils divided by oval pellets, under a band of oval pellets. The rim has eroded zig-zags with an inscription in Runic letters, the only Welsh example, the Runic letters repeated in Lombardic 'Siwurd + Gwlmer'. Bowl is on a massive bell-shaped base with ring moulding at mid height, standing on a finely detailed square base, the coved top moulding with trefoil or fleur-de-lys ornament at corners. Ornate reredos and E end panelling of 1907 with carved vine-scroll cornice and cresting, the side panels with carved lily and passion-flower motifs, the reredos with wheat and vine flanking a cross with canopy. Pulpit, C18 on stone base of c 1904, pine fielded panelled three-sided front. Steps with turned balusters and panelled newels. Rails are wrought-iron with twisted standards and leaf scrolls. Stalls made up from old panelling. Pews have fielded panelled ends, with buttresses, fielded panelled backs and wall-panelling. Oil lamps on turned wooden standards, three on S, four on N. Metal boards with painted texts of Commandments at E end.
Stained glass: E window of four lights to the Rev David Parry died 1877, Nativity, Presentation, Crucifixion and Ascension, and N aisle E window similar. Nave 3-light window c. 1930, by Powell of Whitefriars, Virgin Mary with SS Luke & John. Nave N window to Anne Jordan of Abersenny died 1962, St Mary, by Luxford Studios of New Barnet; N aisle N has two 3-light windows by Taylor & Clifton, one to Thomas family of Abersenny, 1906. Chancel S window, late C19 by Mayer of Munich to AM Story Maskelyne, the Sermon on the Mount. Nave S three-light to W. and M. Davies of Cwmwysg, 1925, by Jones & Willis, Light of the World with SS David and Cynog.
Memorials: Above arcade, draped urn over neo-Grec plaque to Rev Walter Williams of Bayllia, died 1818. Nave memorials to Lewis Howell of Baylie died 1762; Mary Powell of Bailiae died 1739, signed by John William, with painted winged head; Gwellian Havard gent., died 1692. Aisle S wall plaque with three ovals and tiny relief Last Judgment figures to Watkin David Price of Neuadd died 1772, Ann Jones died 1777 and Evan David Price died 1764. Numerous incised floor slabs. N wall plaque to L.M. Downes of Gellybant, Llanddetty, and family from 1837; Jeffrey Williams died 1637 and two other C17 plaques; Jenkin Watkins of Bedwlwyn died 1767; alabaster and marble plaque of 1907 to Rev P Morgan died 1868, and family. E wall Thomas Probert, died 1744, with angle-heads, signed T, Brute; well-lettered plaque to Bridgett Debettot of Stoke Burford Salop died 1738; S wall oval plaque to Anne Hooton died 1746, signed by J. Gwyn. Chancel S marble Gothic memorial to Morgan family 1895; memorial with urn on grey marble, to Rev Thomas Williams of Trephilip died 1856. Neo-Grec memorial to Rev. D. Reynell died 1852 by Jennings of Hereford. Trapezoid neo-Grec memorial to Rev Thomas Williams died 1832; Rebecca and Jane Williams of Trephilip died 1869 and 1871, by king of Hereford; Samuel Jones saddler died 1855 and children to 1899.