ROME — Paolo Violini climbed the steps on his knees.

“See, it’s not difficult,” Mr. Violini, a restoration specialist at the Vatican Museums, said as he slowly shinned up the frescoed stairwell leading up to a once-private papal chapel in Rome. Granted, it was an unusual way to climb a set of stairs. But then again, as Mr. Violini said, these steps were “unique.”

Roman Catholic tradition holds that these are the marble stairs that Jesus climbed at his judgment before the Roman prefect Pontius Pilate. The stairs are said to have been brought to Rome in A.D. 326 from Jerusalem by St. Helena, the mother of Emperor Constantine and collector of all things Jesus. (She also thought she found various remnants of his crucifixion, including nails and wood from the “true cross.”)

It quickly became an attraction for pilgrims, who still make their way up the staircase — housed in a sanctuary across from the Basilica of St. John Lateran — on their knees, as an act of penance as they meditate on the passion of Christ.

But not on the marble itself, which was covered for protection by a walnut wood encasement in 1723. Now, for the first time in 300 years, it is to be revealed to the public by Mr. Violini and church officials on Thursday. The stairs will remain uncovered for two months while the wood casing is being restored.