Here’s my “take” on the Sign of the Cross.
The Sign of the Cross is rich with symbolism. It is the sign of the sacrifice of Christ, the price of our redemption, a manifestation of the love that God had for us, that “while we were yet sinners Christ died for us.” (Rom. 5:8) It professes our faith in the Trinity, a God Who does not exist in isolation but in eternal communion, even before He created anything. Because we are created in the image of this Triune God, we too are created to exist in communion with one another and with God our Creator. This orients us toward self-sacrifice in imitation of Christ. (cf. Eph. 5:1-2) This orientation reminds us that, as Jesus paid with his life to give us the gift of the Mass, so we too pay with our lives: we are called to die to self, in our baptism and every day of our lives. As St. Paul wrote, “we know that our former man was crucified with him.” (Rom. 6:6; cf. Gal. 2:20)
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In the early Church, it was customary to trace the Sign of the Cross upon the forehead (as the book of Revelation suggests). Over time, the Sign began to be made over the whole upper body.
**Head. **God commanded Israel to consecrate priests, prophets, and kings to Him by anointing them on the forehead with oil. We enter into this three-fold office of Christ – as priest, prophet, and king – in our Baptism: after we are washed in the water, we are anointed on the head with oil. As you touch your forehead in the Sign of the Cross, remember the anointing you received in your Baptism. Ask God to sanctify your mind and your thoughts. As your hand moves from your forehead down to your chest, it passes your sensory organs: your eyes, your ears, your nose, and your mouth. With these organs you perceive the revelation of God in nature and in faith. Your whole body has been redeemed by the Cross.
**Torso. **God is all-knowing and sees into the very depths of our souls. We read in Scripture that “God is witness of [our] inmost feelings, and a true observer of [the] heart.” (Wis. 1:6) “Search me, O God, and know my heart!” (Ps. 139:23) The love of God, manifested for us on the Cross, reaches into our deepest inner self. As your hand passes your heart and you touch the bottom of your chest in the Sign of the Cross, you form the vertical beam of the Cross, planting it in your inmost being. Ask God to sanctify your will and your emotions.
**Shoulders. **God liberated Israel from the yoke of slavery they endured in Egypt. The Exodus of the Israelites was a foreshadowing of the Exodus (cf. Luke 9:30-31) on which Christ leads us by his crucifixion: “For freedom Christ has set us free; stand fast therefore, and do not submit again to a yoke of slavery.” (Gal. 5:1) Christ frees us from the yoke of sin and offers us his own in return: “Take my yoke upon you, and learn from me; for I am gentle and lowly in heart, and you will find rest for your souls. For my yoke is easy, and my burden is light.” (Matt. 11:29-30) A yoke is a beam that attaches two animals (often oxen) together to allow them to pull a load, such as a plow. A yoke is never carried alone: we are either yoked to Satan by sin, or we are yoked to Christ by the Cross. As you move your hand from one shoulder to the next in the Sign of the Cross, realize that you are taking the yoke of the Cross upon your shoulders, and that Christ joins himself to you by it. Ask God to sanctify your strength.
You trace upon your body the Cross on which hung the salvation of the world. As the body of Christ hung on the Cross for you, now you willingly take up that cross upon your own body.
In addition to the prayerful action of tracing the cross, there is a hidden prayer in your own fingers. You may have noticed the way the hand of a priest is formed when he makes the Sign of the Cross over the bread and wine in the Eucharistic Prayer, or over the congregation at the blessing at the end of the Mass.
In the time of Pope Innocent III, priests were instructed to make the Sign of the Cross “with three fingers, because the signing is done together with the invocation of the Trinity.” The first three fingers – the thumb, index finger, and middle finger – are held together as a symbol of the unity of the Trinity, three Persons in one God. The other two fingers are curled into the palm, symbolizing the descent of Christ from Heaven to earth and the unity of his two natures, divine and human.
Another way to hold the hand is to keep all five fingers together, signifying the five wounds Christ received during his crucifixion (his two hands, his two feet, and his side). A pious practice observed by some people is, after having made the Sign of the Cross, they place their thumb over their index finger (curling the other three fingers into their palm) thus making a small cross, which they kiss.
However you hold your hand, whatever you call to mind as you make the Sign of the Cross, make it slowly and deliberately. Make it a prayer which encompasses your whole person, body and soul.
Because the gesture of the Sign of the Cross is a testimony to both the Passion and the Resurrection, and the words of the prayer contain a confession of faith in the Trinity, “in the sign of the Cross, together with the invocation of the Trinity, the whole essence of Christianity is summed up.” (The Spirit of the Liturgy, p. 178) To this powerful summary of the faith, what can we say in response but Amen?