Peter and Paul
Eusebius of Caesarea, Ecclesiastical History III.iv.1–2
Paul, in his preaching to the Gentiles, laid the foundations of the churches from Jerusalem round about unto Illyricum. And from the Epistle which we have spoken of as indisputably Peter's . . . it would be clear from his own words in how many provinces he delivered the word of the New Testament by preaching the Gospel of Christ to those of the circumcision.Eusebius, Ecclesiastical History, 1:195.
Nicholas I Mystikos, Stichera to Peter and Paul
He who by his heavenly word changed things on earth to things in heaven, Peter, must be sung today, since it is now that he has returned home: he ran the course of the beautiful feet, he took his upward flight, and from here below he ascended to the One who came down to catch him. He stretched forth his hands to be girded with the girdle of martyrdom, following in the footsteps of his Teacher, whom he had denied before; and offering the catch of his net for a dish on the Divine Table, he received in return the throne of God and judgment upon all nations.
The Sun of the Faith, imbued with the radiance of the Light he persecuted, must be celebrated in song: Paul, the chosen vessel, through whom came to the ends of the earth the fragrance of the ointments of life, waking them up from the torpor of deadly unbelief; that mouth so sweet, the fountain of the deep waters of love, from which the world gathers the precious pearls of tenderness. Now, disciple of Christ, the mirrors taken away and the veils oft he body, you meet God face to face, of whose wounds you bear the mark.Nicholas I Mystikos, Miscellaneous Writings, 113.
George Akropolites, Laudatio Petri et Pauli
The principle disciples of Christ; who changed their names along with their deeds; who bear the keys to the kingdom of Heaven; who ascended to the third heaven; who seized Paradise; the foundations of Christ's Church; who have encompassed the whole world in the preaching of Christ; they: Peter and Paul.George Akropolites, Opera, 2:83.7–12.
The Epistle of Paul to Titus
Paul, servant of God, and an apostle of Jesus Christ, according to the faith of God's elect, and the acknowledging of the truth which is after godliness; in hope of eternal life, which God, that cannot lie, promised before the world began; but hath in due times manifested his word through preaching, which is committed unto me according to the commandment of God our Saviour.
Byzantine homilies and hymns tend to associate saints. Peter and Paul, who also shared a feast day on 29 June. The scene of Peter and Paul embracing, seen in the second example above, symbolizes brotherly love. Seen as key figures in the spread of Christianity, Peter and Paul were frequently depicted together, emphasizing the Byzantine tendency to place the "leaders (koryphaioi) of the apostles," on an equal footing. This contrasts with the West, where Peter, as the first bishop of Rome, was seen as preeminent, which served as a point of contention in the arguments for papal primacy among the five patriarchates.
In the first example above, Paul on the left holds a book representing his epistles. Peter, on the right, holds the keys to the kingdom of Heaven.