Catholic Encyclopedia (1913)/Scala Sancta (Holy Stairs)
Consisting of twenty-eight white marble steps, at Rome, near the Lateran; according to tradition the staircase leading once to the prætorium of Pilate at Jerusalem, hence sanctified by the footsteps of Our Lord during his Passion.
The historians of the monument relate that the Holy Stairs were brought from Jerusalem to Rome about 326 by St. Helena, mother of Constantine the Great. In the Middle Ages they were known as Scala Pilati, the Stairs of Pilate. From old plans it can be gathered that they led to a corridor of the Lateran Palace, near the Chapel of St. Sylvester, were covered with a special roof, and had at their sides other stairs for common use. When Sixtus V in 1589 destroyed the old papal palace and built the new one, he ordered the Holy Stairs be transferred to their present site, before the Sancta Sanctorum (Holy of Holies). The latter is the old private papal chapel, dedicated to St. Lawrence, and the only remaining part of the former Lateran Palace, receiving its name from the many precious relics preserved there. The Sancta Sanctorum also contains the celebrated image of Christ, "not made by human hands", which on certain occasions used to be carried through Rome in procession. These holy treasures, which since Leo X (1513-21) have not been seen by anybody, have recently been the object of learned dissertations by Grisar and Lauer.
In its new site the Scala Sancta is flanked by four other stairs, two on each side, for common use, since the Holy Stairs may only be ascended on the knees, a devotion much in favour with pilgrims and the Roman faithful, especially on Fridays and in Lent. Not a few popes are recorded to have performed this pious exercise; Pius IX, who in 1853 entrusted the Passionist Fathers with the care of the sanctuary, ascended the Holy Stairs on 19 Sept., 1870, the eve of the entrance of the Piedmontese into Rome. Pius VII on 2 Sept., 1817 granted those who ascend the stairs in the prescribed manner an indulgence of nine years for every step. Finally Pius X, on 26 Feb., 1908, granted a plenary indulgence to be gained as often as the stairs are devoutly ascended after confession and communion. Imitations of the Scala Sancta have been erected in various places, as in Lourdes and in some convents of nuns, and indulgences are attached to them by special concessions.