In the Old Testament, for the sacrifices, the priest first raised the victim, and then he moved it along from east to west. This movement formed the figure of the Cross. The High priest, and all other simple priest, blessed the people after the sacrifice doing the same movements. At the time of Ezekiel, when the abominations of Jerusalem were at its peak, a mysterious person received the order to cross the city and mark with the sign T the foreheads of those who cried for the iniquities of that guilty city. All those who were marked with the Sign of Salvation were spared from death. Tertullian and Jerome say: “The Tau Sign, marked on the foreheads of the inhabitants of Jerusalem, who cried for the crimes of that city, protected them against the exterminating angels. The Sign of the Cross on the forehead is an assurance that those who are marked will not be the victims of the devil.” The Philistines had reduced the Israelites to the most humiliating servitude. Samson begins to free them. Unfortunately, the strong one of Israel let himself be surprised, and was chained and blinded. Meanwhile, Samson, meditating on how to take revenge, plans to kill thousands of his enemies in one blow. Providence disposed that he would accomplish his plan making the Sign of the Cross. “Standing in between the two columns that held the building,” says St. Augustine, “the strong one of Israel extends his arms in the form of a Cross. In such an omnipotent attitude, he pushes against the columns, makes them tremble, and destroys his enemies.”
From there and many other examples in the Bible we can see that to pray with the arms extended, forming the Sign of the Cross, has been known from the most remote times of antiquity; and its mysterious omnipotence has been experienced. In a certain sense then, the Sign of the Cross would say what the Savior Himself said: “All power has been given to Me in the Heavens and on the earth.” Heaven itself is disposed in the form of the Sign of the Cross: What do the four cardinal points represent if not the four lines of the cross and the universality of its virtue.
Demons are fallen angels. Their intellect, strength, agility, etc., are superior to ours; their number is incalculable. Jealous that the children of Adam were called to eternal happiness, which they had lost, their only aim and occupation is our destruction, increasing or passions, creating dangerous situations, darkening in us the gift of faith, destroying our moral sense, suffocating our remorse, making us accomplices of their rebellion in order to make us their companions in Hell!!! So, as sure as our battles, and man being in so weak a condition, could it be conceivable that Divine Wisdom would not give us a way to defend ourselves? On the contrary, in order to help us in our battles, God has given to man a powerful and universal weapon that is always at the reach of everyone. What could this weapon be???
Let us question every century, above all the Christian centuries. They respond with a unanimous voice that this weapon is the Sign of the Cross! This weapon had been used by the most learned and holy men in the East as well as in the West. St. John Chrysostom says: “Do not ever go out of your house without making the Sign of the Cross. It will be for you a shield, a weapon, an inexpugnable tower. Neither man nor demon will ever dare to attack you, if they see you clothed with this armor.” Origen says: “The Sign of the Cross is the invisible armor of Christians. Soldier of Christ that you are, wear (use) This Armor always during the day, and during the night, and everywhere. Without It do not undertake any task, whether it be sleeping or traveling, resting or working, eating or drinking, be always clothed with This Protective Armor. Adorn and protect every single one of your members with This Victorious Sign. At the sight of This Sign the infernal powers flee scared and stupefied.” St. Augustine used to say to the Catechumens: “We must confront the enemy with the Symbol and Sign of the Cross; so that the Christian vested with these weapons may easily triumph over the ancient and prideful tyrant.” St. Athanasius says: “By means of the Sign of the Cross the works of magic are made impotent; all the enchantments lose their efficacy. By means of It, the impetus of the most brutal will is moderated and pacified.”