mentioned in the 13th century by Card. Giaconio Gaetano. Ordo
Romanus § 112. A certain love of proportion may have had its share
in the origin of this ceremony, by which the same relative height is
preserved between the Pope and the Cardinal in all cases in which
the former is incensed. Thus also the assistant Bishop, who holds
the Missal for the Pope, kneels when He is seated, and stands when
He stands. We kneel to the Pope to receive his blessing, as we do to
bishops and even priests; we also kneel from respect to his exalted
dignity, not only as sovereign, but also as head of the Catholic
church. It is well known that the British peers kneel even to the
empty throne of their sovereign. Kneeling is a very ancient token of
profound respect; it was paid to Joseph in Egypt, Gen. XLI, 43; to
Elias, 4 Kings I, 13 etc.]

[Footnote 23: "O that an angel" says St. Ambrose, "would appear to
us also, when incensing the altar, and offering sacrifice". Expl. in.
Luc. l. 1, c. 25, n. 9.]

[Footnote 24: Incense is, as we shall see in c. 2; an emblem of
prayer, and in this sense it is offered to the B. Sacrament, to Christ
represented by the crucifix, and adored on the altar. The gospel
is incensed to signify the sweet odour which it communicates to our
souls; and the ministers of God, to signify, according to St. Thomas,
that God maketh manifest _the odour_ of his knowledge by us in every
place: "For we are unto God _the good odour_ of Christ in them who are
saved, and in them who perish". 2 Cor. II, 14, 15. In fine the bread
and wine offered to God are incensed to signify the spices with which
the body of Christ was embalmed in the tomb; such at least is the
explanation given in the Liturgy of St. Chrysostom; and it is from the
oriental churches that the Latin church has taken this last practice.