Christian use The symbol has been used by Christians as a sign of the Holy Trinity (Father, Son and Holy Spirit), especially since the Celtic Revival of the 19th century. When modern designers began to display the triquetra as a stand-alone design, it recalled the three-leafed shamrock which was similarly offered as a trinity symbol by Saint Patrick. Some have also suggested that the triquetra has a similarity to the Christian Ιχθυς symbol. The triquetra has been used extensively on Christian sculpture, vestments, book arts and stained glass. It has been used on the title page and binding of some editions of the New King James Version.
A very common representation of the symbol is with a circle that goes through the three interconnected loops of the Triquetra. The circle emphasizes the unity of the whole combination of the three elements.