21 Things We Do When We Make the Sign of the Cross

From http://catholicexchange.com/21-things-cross

 The Sign of the Cross is a simple gesture yet a profound expression of faith for both Catholic and Orthodox Christians. As Catholics, it’s something we do when we enter a church, after we receive Communion, before meals, and every time we pray. But what exactly are we doing when we make the Sign of the Cross? Here are 21 things:
1. Pray. We begin and end our prayers with the Sign of the Cross, perhaps not realizing that the sign is itself a prayer. If prayer, at its core, is “an uprising of the mind to God,” as St. John Damascene put it, then the Sign of the Cross assuredly qualifies. “No empty gesture, the sign of the cross is a potent prayer that engages the Holy Spirit as the divine advocate and agent of our successful Christian living,” writes Bert Ghezzi.
2. Open ourselves to grace. As a sacramental, the Sign of the Cross prepares us for receiving God’s blessing and disposes us to cooperate with His grace, according to Ghezzi.
3. Sanctify the day. As an act repeated throughout the key moments of each day, the Sign of the Cross sanctifies our day. “At every forward step and movement, at every going in and out, when we put on our clothes and shoes, when we bathe, when we sit at table, when we light the lamps, on couch, on seat, in all the ordinary actions of daily life, we trace upon the forehead the sign,” wrote Tertullian.
4. Commit the whole self to Christ. In moving our hands from our foreheads to our hearts and then both shoulders, we are asking God’s blessing for our mind, our passions and desires, our very bodies. In other words, the Sign of the Cross commits us, body and soul, mind and heart, to Christ. (I’m paraphrasing this Russian Orthodox writer.) “Let it take in your whole being—body, soul, mind, will, thoughts, feelings, your doing and not-doing—and by signing it with the cross strengthen and consecrate the whole in the strength of Christ, in the name of the triune God,” said twentieth century theologian Romano Guardini.
5. Recall the Incarnation. Our movement is downward, from our foreheads to our chest “because Christ descended from the heavens to the earth,” Pope Innocent III wrote in his instructions on making the Sign of the Cross. Holding two fingers together—either the thumb with the ring finger or with index finger—also represents the two natures of Christ.
6. Remember the Passion of Our Lord. Fundamentally, in tracing out the outlines of a cross on ourselves, we are remembering Christ’s crucifixion. This remembrance is deepened if we keep our right hand open, using all five fingers to make the sign—corresponding to the Five Wounds of Christ.
7. Affirm the Trinity. In invoking the name of God the Father, the Son, and the Holy Spirit, we are affirming our belief in a triune God. This is also reinforced by using three fingers to make the sign, according to Pope Innocent III.
8. Focus our prayer on God. One of the temptations in prayer is to address it to God as we conceive of Him—the man upstairs, our buddy, a sort of cosmic genie, etc. When this happens, our prayer becomes more about us than an encounter with the living God. The Sign of the Cross immediately focuses us on the true God, according to Ghezzi: “When we invoke the Trinity, we fix our attention on the God who made us, not on the God we have made. We fling our images aside and address our prayers to God as he has revealed himself to be: Father, Son, and Holy Spirit.”
9. Affirm the procession of Son and Spirit. In first lifting our hand to our forehead we recall that the Father is the first person the Trinity. In lowering our hand we “express that the Son proceeds from the Father.” And, in ending with the Holy Spirit, we signify that the Spirit proceeds from both the Father and the Son, according to Francis de Sales.
10. Confess our faith. In affirming our belief in the Incarnation, the crucifixion, and the Trinity, we are making a sort of mini-confession of faith in words and gestures, proclaiming the core truths of the creed.
11. Invoke the power of God’s name. In Scripture, God’s name carries power. In Philippians 2:10, St. Paul tells us that “at the name of Jesus every knee should bend, of those in heaven and on earth and under the earth.” And, in John 14:13-14, Jesus Himself said, “And whatever you ask in my name, I will do, so that the Father may be glorified in the Son. If you ask anything of me in my name, I will do it.”
12. Crucify ourselves with Christ. Whoever wishes to follow Christ “must deny himself” and “take up his cross” as Jesus told the disciples in Matthew 16:24. “I have been crucified with Christ,” St. Paul writes in Galatians 2:19. “Proclaiming the sign of the cross proclaims our yes to this condition of discipleship,” Ghezzi writes.
13. Ask for support in our suffering. In crossing our shoulders we ask God “to support us—to shoulder us—in our suffering,” Ghezzi writes.
14. Reaffirm our baptism. In using the same words with which we were baptized, the Sign of the Cross is a “summing up and re-acceptance of our baptism,” according to then-Cardinal Joseph Ratzinger.
15. Reverse the curse. The Sign of the Cross recalls the forgiveness of sins and the reversal of the Fall by passing “from the left side of the curse to the right of blessing,” according to de Sales. The movement from left to right also signifies our future passage from present misery to future glory just as Christ “crossed over from death to life and from Hades to Paradise,” Pope Innocent II wrote.
16. Remake ourselves in Christ’s image. In Colossians 3, St. Paul uses the image of clothing to describe how our sinful natures are transformed in Christ. We are to take off the old self and put on the self “which is being renewed … in the image of its creator,” Paul tells us. The Church Fathers saw a connection between this verse and the stripping of Christ on the cross, “teaching that stripping off our old nature in baptism and putting on a new one was a participation in Christ’s stripping at his crucifixion,” Ghezzi writes. He concludes that we can view the Sign of the Cross as “our way of participating in Christ’s stripping at the Crucifixion and his being clothed in glory at his resurrection.” Thus, in making the Sign of the Cross, we are radically identifying ourselves with the entirety of the crucifixion event—not just those parts of it we can accept or that our palatable to our sensibilities.
17. Mark ourselves for Christ. In ancient Greek, the word for sign was sphragis, which was also a mark of ownership, according to Ghezzi. “For example, a shepherd marked his sheep as his property with a brand that he called a sphragis,” Ghezzi writes. In making the Sign of the Cross, we mark ourselves as belong to Christ, our true shepherd.
18. Soldier on for Christ. The sphragis was also the term for a general’s name that would be tattooed on his soldiers, according to Ghezzi. This too is an apt metaphor for the Christian life: while we can be compared to sheep in the sense of following Christ as our shepherd we are not called to be sheepish. We instead are called to be soldiers of Christ. As St. Paul wrote in Ephesians 6, “Put on the armor of God so that you may be able to stand firm against the tactics of the devil. … take the helmet of salvation and the sword of the Spirit, which is the word of God.”
19. Ward off the devil. The Sign of the Cross is one of the very weapons we use in that battle with the devil. As one medieval preacher named Aelfric declared, “A man may wave about wonderfully with his hands without creating any blessing unless he make the sign of the cross. But, if he do, the fiend will soon be frightened on account of the victorious token.” In another statement, attributed to St. John Chrysostom, demons are said to “fly away” at the Sign of the Cross “dreading it as a staff that they are beaten with.” (Source: Catholic Encyclopedia.)
20. Seal ourselves in the Spirit. In the New Testament, the word sphragis, mentioned above, is also sometimes translated as seal, as in 2 Corinthians 1:22, where St. Paul writes that, “the one who gives us security with you in Christ and who anointed us is God; he has also put his seal upon us and given the Spirit in our hearts as a first installment.” In making the Sign of the Cross, we are once again sealing ourselves in the Spirit, invoking His powerful intervention in our lives.
21. Witness to others. As a gesture often made in public, the Sign of the Cross is a simple way to witness our faith to others. “Let us not then be ashamed to confess the Crucified. Be the Cross our seal made with boldness by our fingers on our brow, and on everything; over the bread we eat, and the cups we drink; in our comings in, and goings out; before our sleep, when we lie down and when we rise up; when we are in the way, and when we are still,” wrote St. Cyril of Jerusalem.

Sources include: The Sign of the Cross, by Bert Ghezzi, and Signs of Life, by Scott Hahn