Celtic Knot with Triquetra in Circle Wood CarvingCeltic Knot with Triquetra in Circle Wood Carving. The Triquetra symbol represents the number three which was magical to the Celts. This symbol was adopted by the Christians in the 4th Century as a trinity symbol when the Bishop Hilary of Poitiers, a famous Celtic theologian, introduced the concept of Holy Trinity. Dimensions: 12" Diameter x 1" Deep Carved Wood Mahogany