One of the smallest celtic knots is known as Solomon’s knot. It probably got its name from the monks of the Middle Ages. In their eyes it could have symbolised the wisdom of Solomon - most likely it suggested to them how polarities like life and death, light and darkness, finite and infinite were incorporated in a concept of one God.
Solomon’s knot belongs to a group of knots based on the square or cross and it is said to refer to the life-giving energy of the Earth. If we use the centre of the four-sided square then we also have to deal with the number five, which is for instance symbolised in the Pentagram. Depending on your viewpoint it is possible to see countless other meanings.