On the Bishop’s Procession
After the bells have sounded, the vested pontiff proceeds, seven acolytes with lights preceding him and seven sub-deacons coming after with lectionaries [cum plenariis] . And after these seven deacons advance, followed by twelve priors. After these three acolytes come with thuribles bearing incense. After these the Gospel book is borne before the bishop, who follows it walking between two others, accompanied by the princes and the people. As they enter the choir, they are met with the verse Gloria Patri sung by the cantors, to whom the bishop extends the peace. Then he goes to the altar and when the chant is finished he says the prayer [oratio] and then goes to his seat. Some of the ministers sit with him, and others wait on him: [all of] this is to demonstrate the presence of Christ for us 
 The Proper and Ordinary chants are tied intimately to the ritual action of the Mass. The Introit, as its name suggests, is a processional chant that accompanies the pontiff’s entrance into the sanctuary. The ceremony described here by Honorius differs only slightly from the account given by the Ordo Romanus Primus, the earliest witness we have to the Roman liturgical tradition, which specify that the Introit verses be sung until the pontiff has arrived in the choir and given the signal for the Gloria Patri. Fr. Quoex briefly explains the ancient papal entrance:
“The pope moves toward the altar in procession. In front of him walk the sub-deacon sequens holding the incensor and the seven regional acolytes, each one with a candlestick. The procession arrives at the entrance to the choir where the choir is standing. The pontiff advances between the two columns of chanters to the level of the first chanters (“in caput scolae”). He bows toward the altar, straightens himself, prays a moment in silence, signs himself on the head, and gives the kiss of peace to his assistants. Then he gives the sign to the choir master to say “gloria [Patri]”; the choir master bows and complies while the pope mounts into the apse. Meanwhile, the archiparaphist has rolled out the oratorium, a sort of “prayer mat,” before the steps of the altar. In so doing, the archiparaphonist executes a ceremonial action, linked to a precise moment of liturgical chant. Arrived before the altar, the pope prostrates himself on the oratorium during the chant gloria [Patri] until the repetition of the Introit verset (n. 50).”
De processione episcopi.
Postquam campanae sonaverint, pontifex ornatus procedit, quem septem acolythi cum luminibus praeeunt, post quos septem subdiaconi cum plenariis incedunt. Item post hos septem diaconi gradiuntur, quos duodecim priores sequuntur. Post hos tres acolyti cum thuribulis vadunt, qui incensum gerunt. Post quos Evangelium ante episcopum fertur, quod ipse inter duos ambulans sequitur, eumque principes cum populo comitantur. Qui, dum chorum ingreditur, a cantoribus cum versu, Gloria Patri, excipitur, Quibus ipse pacem porrigit, deinde ad altare vadit, finito cantu orationem dicit, et tunc sedere pergit. Quidam de ministris cum eo sedent, quidam ei assistunt: hoc quasi praesentiam Christi nobis exhibet.