“Concerning those who call themselves Cathari, if they come over to the Catholic and Apostolic Church, the great and holy Synod decrees that they who are ordained shall continue as they are in the clergy. But it is before all things necessary that they should profess in writing that they will observe and follow the dogmas of the Catholic and Apostolic Church; in particular that they will communicate with persons who have been twice married, and with those who having lapsed in persecution have had a period [of penance] laid upon them, and a time [of restoration] fixed so that in all things they will follow the dogmas of the Catholic Church…” Council of Nicaea I (A.D. 325).
“Concerning this **Holy Catholic Church **Paul writes to Timothy, ‘That thou mayest know haw thou oughtest to behave thyself in the House of God, which is the Church of the Living God, the pillar and ground of the truth’” Cyril of Jerusalem, Catechetical Lectures,18:25(A.D. 350).
"[T]he Article, In one Holy Catholic Church,’ on which, though one might say many things, we will speak but briefly. It is called Catholic then because it extends over all the world, from one end of the earth to the other; and because it teaches universally and completely one and all the doctrines which ought to come to men’s knowledge, concerning things both visible and invisible, heavenly and earthly… for this cause the Faith has securely delivered to thee now the Article, And** in one Holy Catholic Church**;’ that thou mayest avoid their wretched meetings, and ever abide with the Holy Church Catholic in which thou wast regenerated. And if ever thou art sojourning in cities, inquire not simply where the Lord’s House is (for the other sects of the profane also attempt to call their own dens houses of the Lord), nor merely where the Church is, but where is the Catholic Church. For this is the peculiar name of this Holy Church, the mother of us all, which is the spouse of our Lord Jesus Christ, the Only-begotten Son of God.” Cyril of Jerusalem, Catechetical Lectures, 18:23,26 (A.D. 350).
“I believe in the Holy Spirit, the holy Catholic Church, the communion of saints, the remission of sins, the resurrection of the flesh, and eternal life. Amen.” Apostles Creed (A.D. 360).
“And in the Holy Spirit, the Lord, the life-giver, Who proceeds from the Father, Who with the Father and the Son is together worshiped and together glorified, Who spoke through the prophets; in one holy Catholic, and apostolic Church.” Constantinopolitan Creed (A.D. 381).
“Those who from heresy turn to orthodoxy, and to the portion of those who are being saved, we receive according to the following method and custom: Arians, and Macedonians, and Sabbatians, and Novatians, who call themselves Cathari or Aristori, and Quarto-decimans or Tetradites, and Apollinarians, we receive, upon their giving a written renunciation [of their errors] and anathematize every heresy which is not in accordance with the Holy, Catholic, and Apostolic Church of God.” Council of Constantinople I, Canon 7 (A.D. 381).
“We must hold to the Christian religion and to communication in her Church, which is Catholic and which is called Catholic not only by her own members but even by all her enemies. For when heretics or the adherents of schisms talk about her, not among themselves but with strangers, willy-nilly they call her nothing else but Catholic. For they will not be understood unless they distinguish her by this name which the whole world employs in her regard.” Augustine, The True Religion, 7:12 (A.D. 390).
“Inasmuch, I repeat, as this is the case, we believe also in the Holy Church, [intending thereby] assuredly the Catholic. For both heretics and schismatics style their congregations churches. But heretics, in holding false opinions regarding God, do injury to the faith itself; while schismatics, on the other hand, in wicked separations break off from brotherly charity, although they may believe just what we believe. Wherefore neither do the heretics belong to the Church catholic, which loves God; nor do the schismatics form a part of the same.” Augustine, On Faith and Creed, 10:21 (A.D. 393).
“For in the Catholic Church, not to speak of the purest wisdom, to the knowledge of which a few spiritual, men attain in this life…–not to speak of this wisdom, which you do not believe to be in the Catholic Church, there are many other things which most justly keep me in her bosom. The consent of peoples and nations…so does her authority…the succession of priests…[a]nd so, lastly, does the name itself of Catholic, which, not without reason, amid so many heresies, the Church has thus retained; so that, *though all heretics *wish to be called Catholics, yet when a stranger asks where the Catholic Church meets, no heretic will venture to point to his own chapel or house. Such then in number and importance are the precious ties belonging to the Christian name which keep a believer in the Catholic Church…Now if the truth is so clearly proved as to leave no possibility of doubt, it must be set before all the things that keep me in the Catholic Church…For my part, I should not believe the gospel except as moved by the authority of the Catholic Church…for it was through the Catholics that I got my faith in it; and so, whatever you bring from the gospel will no longer have any weight with me. Wherefore, if no clear proof of the apostleship of Manichaeus is found in the gospel, I will believe the Catholics rather than you.” Augustine, Against the Epistle of Manichaeus, 4:5,5:6 (A.D 397).