Pope Francis celebrates Mass for the Solemnity of Pentecost at the Altar of the Chair inside St. Peter's Basilica, on May 31, 2020.

Pope Francis celebrates Mass for the Solemnity of Pentecost at the Altar of the Chair inside St. Peter's Basilica, on May 31, 2020.

Until now, the 45 altars and 11 chapels in St. Peter’s Basilica have been used every morning by priests to celebrate their daily Mass.