A prayer rope is a rope tied in knots that is used to aid in prayer. The way I have been taught is to say the Jesus prayer (“Lord Jesus Christ, Son of God, have mercy on me, a sinner”) on each knot. Then when you get to the last knot (33, 50, 100, whatever it is) you know you have prayed it that many times. But there are other similar ways of using it, it is not a hard and fast rule.
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