In the apse behind the altar is the episcopal throne assembled under the direction of the antiquary Cardinal Baronius, reusing lions, in the Cosmatesque style that is associated with the Vassalletto school, which support the armrests; on the backrest is inscribed the opening and closing words of the twenty-eighth homily of St. Gregory the Great, inscribed under the mistaken tradition that he preached them here, in front of the relics of Sts. Nereus and Achilleus on their feast day. When Cardinal Baronio ordered the inscription, he did not know that the relics were originally buried in the underground basilica of the Catacomb of Domitilla, so thought that this was the place St Gregory preached.