The sign of the cross is a beautiful gesture which reminds the faithful of both the cross of salvation while invoking the Holy Trinity. Technically, the sign of the cross is a sacramental, a sacred sign instituted by the Church which prepares a person to receive grace and which sanctifies a moment or circumstance. Along this thought, this gesture has been used since the earliest times of the Church to begin and to conclude prayer and the Mass.
The early Church Fathers attested to the use of the sign of the cross. Tertullian (d. c. 250) described the commonness of the sign of the cross: “In all our travels and movements, in all our coming in and going out, in putting on our shoes, at the bath, at the table, in lighting our candles, in lying down, in sitting down, whatever employment occupies us, we mark our foreheads with the sign of the cross" (De corona, 30).
St. Cyril of Jerusalem (d. 386) in his Catechetical Lectures stated, “Let us then not be ashamed to confess the Crucified. Be the cross our seal, made with boldness by our fingers on our brow and in everything; over the bread we eat and the cups we drink, in our comings and in our goings out; before our sleep, when we lie down and when we awake; when we are traveling, and when we are at rest" (Catecheses, 13). Gradually, about the ninth century, the sign of the cross was incorporated in different acts of the Mass, such as the three-fold signing of the forehead, lips, and heart at the reading of the gospel or the blessing and signing of the bread and wine to be offered.
The earliest formalized way of making the sign of the cross appeared about the 400s, during the Monophysite heresy which denied the two natures in the divine person of Christ and thereby the unity of the Holy Trinity. The sign of the cross was made from forehead to chest, and then from right shoulder to left shoulder with the right hand. The thumb, forefinger, and middle fingers were held together to symbolize the Holy Trinity– Father, Son, and Holy Spirit. Moreover, these fingers were held in such a way that they represented the Greek abbreviation I X C (Iesus Christus Soter, Jesus Christ Savior): the straight forefinger representing the I; the middle finger crossed with the thumb, the X; and the bent middle finger, the C. The ring finger and “pinky" finger were bent downward against the palm, and symbolize the unity of the human nature and divine nature, and the human will and divine will in the person of Christ. This practice was universal for the whole Church until about the twelfth century, but continues to be the practice for the Eastern Rites of the Catholic Church and the Orthodox Churches.
An instruction of Pope Innocent III (1198-1216) evidences the traditional practice but also indicates a shift in the Latin Rite practice of the Catholic Church: “The sign of the cross is made with three fingers, because the signing is done together with the invocation of the Trinity. …This is how it is done: from above to below, and from the right to the left, because Christ descended from the heavens to the earth, and from the Jews (right) He passed to the Gentiles (left)." While noting the custom of making the cross from the right to the left shoulder was for both the western and eastern Churches, Pope Innocent continued, “Others, however, make the sign of the cross from the left to the right, because from misery (left) we must cross over to glory (right), just as Christ crossed over from death to life, and from Hades to Paradise. [Some priests] do it this way so that they and the people will be signing themselves in the same way. You can easily verify this– picture the priest facing the people for the blessing– when we make the sign of the cross over the people, it is from left to right…." Therefore, about this time, the faithful began to imitate the priest imparting the blessing, going from the left shoulder to the right shoulder with an open hand. Eventually, this practice became the custom for the Western Church.
In the classic work, The Ceremonies of the Roman Rite by Adrian Fortescue and J. B. O’Connell, the sign of the cross is made as follows: “Place the left hand extended under the breast. Hold the right hand extended also. At the word Patris [Father] raise it and touch the forehead; at Filii [Son] touch the breast at a sufficient distrance down, but above the left hand; at Spiritus Sancti [Holy Spirit] touch the left and right shoulders; atAmen join the hands if they are to be joined." Although this practice may have evolved from the original and still current practice of Eastern Rite, it nevertheless has been the standing custom for the Latin Rite Church for centuries.
No matter how one technically makes the sign of the cross, the gesture should be made consciously and devoutly. The individual must be mindful of the Holy Trinity, that central dogma that makes Christians “Christians." Also, the individual must remember that the cross is the sign of our salvation: Jesus Christ, true God who became true man, offered the perfect sacrifice for our redemption from sin on the altar of the cross. This simple yet profound act makes each person mindful of the great love of God for us, a love that is stronger than death and promises everlasting life. The sign of the cross should be made with purpose and precision, not hastily or carelessly.