The Apse at St. Praxedes, Rome
Basilica of St. Praxedes, Rome
On the outermost, "triumphal" arch angels conduct the elect to the Heavenly Jerusalem. Within two open the gates, the apostles, the Virgin, and St. Praxedes come from left and right offering their crowns to Christ, who stands in the center in a reddish garment with St. Praxedes and the Virgin Mary.
The approach of the saints is suggested by the concluding chapter of Revelation: "Blessed are they that wash their robes in the blood of the Lamb: that they may have a right to the tree of life, and may enter in by the gates into the city" (verse 14). For the angels guarding the gates, see Revelation 21:12, "it had a wall great and high, having twelve gates, and in the gates twelve angels." The offering of the crowns is suggested by Revelation 4:10: "The four and twenty ancients fell down before him that sitteth on the throne, and adored him that liveth for ever and ever, and cast their crowns before the throne."
The next, "apsidal" arch continues the references to Revelation. In the upper register Christ as the Lamb is flanked by angels and the creatures symbolizing the four evangelists (Revelation 4:6-7). In the lower register the 24 elders of Revelation prepare to offer their crowns to the Lamb (Revelation 4:11).
Finally, in the apsidal basin:
References to Revelation continue as Saints Praxedes and Pudentiana bring their golden martyr's crowns to Christ. This corresponds to Revelation 4:4,10, where the 24 elders put their golden crowns before the Heavenly Throne. The wavy shapes behind the figure of Christ may also correspond to the "sea of glass like crystal" before the Throne in Revelation 4:6.
Saints Peter and Paul present Praxedes and Pudentiana to Christ. On the far left, with a square halo because he was alive at the time of this mosaic, Pope Paschal I holds a maquette of the present church building, which he had constructed. The maquette and the crowns all sit on cloth napkins, emblematic of a gift to or from an emperor. On the far right is a deacon saint, probably St. Lawrence.
A phoenix, symbol of Christ in the Resurrection, sits on a branch of the palm tree on the left. From the cloud at the summit, the hand of the Father reaches down with a crown for the Son, perhaps recalling Psalm 21:4, "For thou hast prevented [welcomed] him with blessings of sweetness: thou hast set on his head a crown of precious stones."
The photo of the entire apse with arches in full resolution
Detail photograph and further commentary on the outer arch
Detail photographs and commentaries on the apsidal basin:
Photographed at the basilica by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.