Cuthbert was originally a Celtic Christian. That connection, plus the similarity in shape, gives this cross the alternative name; Thor's Cross
Cuthbert means 'brilliant light', which leads nicely to the story about St. Cuthbert.
One night in August, 651, the shepherd boy Cuthbert was praying on a hillside near Melrose monastery which lies at the heart of the Scottish Borders. He saw "a great light and a choir of angels" descend from the night sky. The next day he learned that St. Aidan, Bishop of Lindisfarne, had died the previous night. Cuthbert believed he had witnessed St. Aidan's soul being carried to heaven and took this as a sign of his calling to missionary work. He became Bishop of Lindisfarne on Easter Day, 685. Many miraculous healings have been attributed to St. Cuthbert and his remains now lie in Durham Cathedral.
The St. Cuthbert Cross is seen mainly on heraldic regalia and similar ceremonial wear. To fit the shape of escutcheons (shields) in coats-of-arms, the cross has four equal-length arms. Each arm has a Thor-like hammer head. There is no connection between Thor and St. Cuthbert, except for the influence of Celtic art in the seventh century. Cuthbert was originally a Celtic Christian, before adopting Roman rites in 661.
This cross is sometimes confused with the Consecration Cross.