To some of the Ethiopian Churches visited, some displayed knotwork designs, much like those of the Celtic, Anglo-Saxon and Viking cultures of Britain, but instead of curving interlocking lines, they are based upon geometric squares or rectangles, i.e. right angles, along with cross shapes included. These are also similar to Islamic type religious designs, but this type is most likely unique to Ethiopia.
Again the crosses ward off evil, but the knotwork patterns are also symbolic of endless lines, overlapping and weaving inside and outside of each other, and as such present a malevolent entity with not only the cross but also a never-ending puzzle, which it is thought would entrap the evil spirit for eternity, as it follows the endless lines.
A better term for these rectilinear knotwork geometric patterns used for spiritual defence, here in Ethiopia, is the ‘labyrinthine meander’, which is the term used to describe similar meandering designs on Greek and Roman buildings, pottery, mosaics, etc.
What better way to entrap a demon than to give it an endless series of meandering labyrinthic like lines, including crosses, for it to become eternally lost and confused in the elaborate and intricate maze like spiritual protective design.

A Labyrinthic Meandering with Crosses Apotropaic Window at Debra Selam Mikael Timber Cave Church, 8th Century AD, Tigray

A Curving Labyrinthic Meandering with Crosses Apotropaic Window at Yimrahanna Kristos Cave Church, Early 11th Century AD, Lalibela

Painted Labyrinthic Meandering Ceiling Design at Makina Medhane Alam Cave Church, 12th/13th Century AD

A Painted Labyrinthic Meandering Ceiling Design at Makina Medhane Alam Cave Church, 12th/13th Century AD

A Carved Labyrinthic Meandering with Crosses Apotropaic Door at Mikael Imba Rock-Hewn Church, 8th Century AD, Tigray

Carved Labyrinthic Meandering Panels to an Apotropaic Rood Screen or similar at Mikael Imba Rock-Hewn Church, 8th Century AD, Tigray
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