St Paisios the Athonite

How great is the power of the cross! Because of course on it is the Crucified Christ.

That's why there is nothing more valuable than your baptismal cross! It is blessed in your name, and do not give it to anyone else. Not even for a moment take the cross off.
Not even when bathing, on the grounds that dirty water will spill on the cross. And what to do? Just as much water purifies the cross. Without it, evil can strike you! Not even when you have marital contacts take it off.
- You have to make your cross correctly. When you don't do it right, the evil spirits not only don't leave but laugh. And the Virgin Mary is angry. When you make the sign of the cross, you have to put your right hand first on the forehead, then on the navel, then on the right shoulder and then on the left. The one who puts his hand not on the navel but in the heart  turns it upside down. Don't make the sign of the cross on yourself in the air either. The hand must touch the body. And when you are crossed, you must pray. Otherwise, that's how the actors are crossed.

You must cross everything except the Holy Chalice of Divine Communion. If something is thrown in the street, it may be cunning. If you see that someone else has crossed it, then you don't need to do it either. If you don't want to confuse those who see you and don't understand you, then you can the sign of the cross with your eyes.

- One day someone gave an apple to a believer and he immediately ate it. And the Elder scolded him:

-How easy it is for them to destroy you! Even if an angel gave it to you, you have to cross it first.

I once asked the Elder:

-When we yawn, what happens? What is transmitted?

-When you yawn, it's good. But you have to cross your mouth. I have no right to reveal to you exactly what is happening and what is being transmitted. It does not suit. It's a mystery.

St. Paisios the Athonite