The Coptic Synaxarian calls Peter "head of the apostles." [PO. 16:313].
A notice for the feast of Ss. Peter and Paul on 5 Abib, or June 29, reads:
"...when [the Lord] chose Peter, He made him first of the disciples..........Then the Lord gave him the best part, established him as cornerstone of the Church....." [PO 17:622-3].
The Coptic Synaxarian commemorates Peter's confession on 7 Mesore, or July 31 and says:
"....Peter became the head of the disciples, and lieutenant [sic] at Rome, for the authority over all the heads of the world...." [PO 17:710].
The Ethiopian Synaxarian commorates St. Peter on 7 Nahase [August 13] and refers to him as "head of the apostles.....He [Peter] is established over all the princes of the world, the patriarchs, metropolitans, bishops, priests, deacons, and the entire priestly clerical order..." [PO 9:291-2].
PETER AND PAUL
In the tradition of the Church, Saints Peter and Paul enjoy a certain distinction within the apostolic choir: they are leaders or "chiefest" of the apostles. Several fathers use this language; for example Venantius Fortunatus, the Latin hymnographer, proclaimed:
"[Paul] was more learned in his admonitions; [Peter] was higher in rank......the one opens the way to heaven by his teachings, the other by the key." [Miscellanea III, 7. PL 88:126].
Peter was prince by virtue of the key; Paul was also first by his teaching. [Miscellanea IX, 2. PL 88:299].
There are also many testimonies to Saint Peter's primacy in the Syriac liturgies, but that will have to wait for another day. He is also given primacy in west Syrian liturgies.
Saint Leo
"The right of using this authority passed on to the other apostles, but what is intimated to all is, not without reason, commended to one. For this [authority] is singularly entrusted to Peter, because the form of Peter is set before all the rulers of the Church. The priviledge of Peter remains, therefore, wherever judgement is passed through his equity, nor is there excessive severity or remission where nothing shall be bound, nothing loosed, what Blessed Peter shall have either bound or loosed." [Sermon 83: PL 54:430].
The Greek Church celebrated the feast of the chains of St. Peter on January 16. The text venerates Peter as the coryphaeus, "rock of the faith," "key bearer," protothrone," and "law-giver, shepherd and teacher of Christ's flock." [Menaion, Athens 1979, January, 138-45].
Note: According to Liddell and Scott, a standard Greek lexicon, the term "coryphaeus" or "koruphaios," comes from Attic drama and "refers to the leader of the chorus, and means "foremost man, leader, chief." [Oxford University Press 1933, s.v.].
Texts for the feast of Ss. Peter and Paul, on June 29, refer to Peter as the leader [prostates] of the Church, the "great president," to whom Christ "entrusted the helm of the Church." [Pitra, LXXIII, LXXVI].
Texts for the commoration of all the apostles, on June 30, call Peter the "foundation of all the faithful," exarch of the apostles," and "divine and sacred head." [Ed. J.B. Pitra, op. cit., XIII, XVII].
A tenth century Byzantine Menology, published by B. Latysev, is strikingly reminiscent of the thinking of St. John Chrysostomos. On June 29, feast of saints Peter and Paul, it has the following notice about St. Peter, alluding to his fall and restoration:
"...and see, he learns to be patient to sinners, and he received simply the diocese of the whole world..."[Menologii Anonymi Byzantini Saeculi X Quae Supersunt, Petropolis, 1911-1912. Fasc. II, 115].
An Armenian Synaxarion attributed to to Catholicos Gregory VII of Anawarza [c.1300] commemorates, on 9 Aratz [January 6], a feast in honor of the chains of Peter, "head" of the apostles and rock of the Church." The Gregorian Synaxiarian calls Peter "head of the apostles."[PO 19:46, 734].
An Egyptian source from the early seventh century remarks that God made a promise, "saying to the chosen one and head of the apostles," Peter: "Thou art a rock, and upon it I shall build my church." [Chronicle of Michael the Syrian, Bk X, 26. Ed. J. Chabot, 2:284].