127. The journey of Lent ends with the Easter Triduum, initiated by the celebration of the Coena Domini Mass. During the Triduum, Good Friday which is dedicated to the celebration of the Lord's Passion, is eminently suited for the "Adoration of the Holy Cross".
Popular piety tends to anticipate the cultic veneration of the Cross. Throughout Lent, every Friday is observed, since very ancient times, as a commemoration of the Lord's Passion and the faithful easily direct their devotions towards the mystery of the Cross.
They contemplate the crucified Saviour, they sense more easily the great suffering which Jesus, the Holy and Innocent One, suffered for the salvation of mankind. They understand his love and the effectiveness of his redemptive sacrifice.
128. The various and numerous devotions to the crucified Christ acquire a special significance in those churches dedicated to the mystery of the Cross or where authentic relics of the true cross are venerated. The "invention of the Cross" in the early fourth century, and the subsequent diffusion throughout the Church of particles of the true Cross, gave notable impulse to devotion to the Cross.
Devotions to the crucified Christ contain many elements usually found in popular piety: hymns and prayers, acts such as the unveiling and kissing of the Cross, processions and blessing with the Cross. These can lead to the development of pious exercises often containing many valuable formal and material elements.
Devotion to the Cross, however, sometimes requires a certain enlightenment. The faithful should be taught to place the Cross in its essential reference to the Resurrection of Christ: the Cross, the empty tomb, the Death and Resurrection of Christ are indispensable in the Gospel narrative of God's salvific plan. In the Christian faith, the Cross is an expression of the triumph of Christ over the powers of darkness. Hence, it is adorned with precious stones and is a sign of blessing when made upon one's self, or on others or on objects.
129. The Gospel texts of the Passion are especially detailed. Coupled with a tendency in popular piety to isolate specific moments of the narrative, this has induced the faithful to turn their attention to specific aspects of the Passion of Christ, making of them specific devotions: devotion to the "Ecce Homo", Christ despised, "crowned with thorns and clothed in a purple cloak" (John 19, 5), and shown to the multitude by Pilate; devotion to the five sacred wounds of Christ, especially to the side of Christ from which flowed blood and water for the salvation of mankind (John 19, 34); devotion to the instruments of the Passion, the pillar at which Christ was scourged, the steps of the Praetorium, the crown of thorns, the nails, the lance that pierced Him; devotion to the Holy Shroud.
Such expressions of piety, often promoted by persons of great sanctity, are legitimate. However, in order to avoid excessive fragmentation in contemplation of the mystery of the Cross, it is always useful to emphasize the whole event of the Passion, as is the case in biblical and patristic tradition.
From the Directory on Popular Piety and the Liturgy