Celtic knots are a variety of stylized endless knots used for decoration. Though Celtic knot designs are dated to pre-Christianity, they are well known for their use in the ornamentation of Christian monuments and manuscripts such as the 8th century Book of Kells.

There is no definitive guide as to the meaning of Celtic knots, but it is generally accepted that the looping Celtic knot design denotes eternity and interconnectedness.

The Trinity knot predates Christianity and was likely a Celtic symbol of the triple aspects of the Goddess (Maiden, Mother and Crone). It also makes an ideal Christian symbol as the representation of the concept of "three in one" in the Christian trinity belief (Father, Son, and Holy Ghost).