Roman Catholics make the sign of the cross in the following order: The right hand moves from top (forehead) to bottom (chest) and then from left (left shoulder) to right (right shoulder). Most Eastern Christians do it in a different order: From top to bottom and then from right to left.
There are several theological interpretations of that difference. The biblical meaning of “the left side” is different from “the right side”. In a simplified manner we could say that in the biblical world-view the right side is good, noble, and heavenly, while the left is bad, low, and earthly. (I do not need to tell you that this approach can still be found in the English word “right”.) Against this background we can easily imagine a large symbolic difference depending on whether you move from left or right (symbol of ascension) or from right to left (symbol of incarnation).
But there is also a more historical approach. How did the difference between the Eastern and the Western practice emerge?
As far as I know, bishops (and priests) in the Roman Empire have always made the sign of the cross as a blessing over the people by writing the sign of the cross in the air. After moving from top to bottom they move from left to right. Why? Because this is the natural way of writing. Greek and Latin words – these two languages have always been dominant in the Roman Empire – are written from left to right.
What do the people do when they are blessed in that way? They do what is natural to them: They mirror the sign. So they move from right to left (sic!). Check it out with a little child: When you stand vis-à-vis to a kid and try to demonstrate the sign of the cross, the kid will mirror your movements. If you move from left to right, the kid will move from right to left. – That is why I know a lady who taught her grandchildren the sign of the cross sitting next to them, not vis-à-vis.
In this context, the movement from left to right is only done by those who write the sign into the air as a blessing over others. In all other cases the movement goes from right to left – even in private prayer: I do not bless myself, I am being blessed.
Around 1190 a Roman deacon – who later became Pope Innocence III – witnessed that some people in Rome have started to make the sign over their bodies in the opposite direction: from left to right. Since then, moving from the left shoulder to the right shoulder has become the typical Western way.
But why did these people start to change the direction? They started to reflect too much. “Look, the bishop moves his hand from left to right, so we should do the same!” Or, following another theory that refers to the different order of words in the Greek and Latin clause for “Holy Spirit”: “Look, when the Greek say ‘holy’ they touch the right shoulder, so we should do the same!” Anyway: The natural mirror effect was replaced by something on a higher level of reflection.
Nowadays the movement during a Roman Catholic blessing is always in a way distorted. This gets very obvious when a priest stands close to you and blesses you individually. While he writes the cross in the air, you criss-cross his movement with your own hand. In no way is this a natural gestural communication. Instead of intuitively mirroring the sign that is written over us, we got used to imitate the blessing gesture on our own bodies.
Someone in the 12th century started to change the direction of the movement. My personal plan is to be “someone in the 21st century” who starts to reverse that development. I always make the sign of the cross from right to left. When a bishop or priest makes the blessing sign from left to right, it feels natural to mirror that sign by moving from right to left. During this movement my arm goes from a cramped position (right fingers on the right shoulder) to an open and wide position (right fingers on the left shoulder) – maybe a nice symbol for spiritual development!
Is anyone going to join me? (But please do not ask me what you should do when you are a lefty.)