Security was a Knotted Rope

For many hundreds of years, cords of ropes made of rush and fiber were used to "lock" doors and tie up walls. The legend goes, a knotted rope became a famous symbol of security. Intricately tied by Gordius, King of Phrygia, and known by his name, the Gordian Knot, secured the yoke to the shaft of his chariot. Its untying was pronounced by oracles to be possible only by the man destined to conquer Asia. However, when Alexander the Great failed to undo the Gordian Knot, he cut it swiftly with his sword, giving us the expression, "to cut the Gordian Knot," meaning a bold, decisive action, effective when milder measures fail.