Primary Sources:

The Early Church Period

Nero's persecution of Christians     Tacitus, The Annals, 44.2-44.5:
Persecution of Christians under Nero after the fire: "Yet no human effort, no princely largess nor offerings to the gods could make that infamous rumor disappear that Nero had somehow ordered the fire. Therefore, in order to abolish that rumor, Nero falsely accused and executed with the most exquisite punishments those people called Christians, who were infamous for their abominations. . . . Therefore, first those were seized who admitted their faith, and then, using the information they provided, a vast multitude were convicted, not so much for the crime of burning the city, but for hatred of the human race. And perishing they were additionally made into sports: they were killed by dogs by having the hides of beasts attached to them, or they were nailed to crosses or set aflame and when the daylight passed away, they were used as nighttime lamps. Nero gave his own gardens for this spectacle and performed a Circus game, in the habit of a charioteer mixing with the plebs or driving about the race-course. Even though they were clearly guilty and merited being made the most recent example of the consequences of crimes, people began to pity these sufferers, because they were consumed not for the public good but on account of the fierceness of one man."

Martyrdom of Peter and Paul
"Paul was beheaded on the Ostesian road. And Peter, having come to the cross, said: Since my Lord Jesus Christ, who came down from the heaven upon the earth, was raised upon the cross upright, and he has deigned to call to heaven me, who am of the earth, my cross ought to be fixed head down most, so as to direct my feet towards heaven; for I am not worthy to be crucified like my Lord. Then having reversed the cross, they nailed his feet up." From Acts of Peter and Paul.

Release of John from Patmos     Eusebius quotes Tertullian concerning the end of persecutions after the death of Domitian, and the subsequent release of John from Patmos in his Church History 3:20:10:
"But after Domitian had reigned fifteen years, and Nerve had succeeded to the empire, the Roman Senate, according to the writers that record the history of those days, voted that Domitian's honors should be cancelled, and that those who had been unjustly banished should return to their homes and have their property restored to them. It was at this time that the apostle John returned from his banishment in the island and took up his abode at Ephesus, according to an ancient Christian tradition."

Letters from Pliny to Trajan and Trajan to Pliny     
Pliny to the Emperor
"I have never been present at the trial of Christians. For that reason I do not know what or how much to punish or to ask. I have hesitated no little whether any distinction should be made for age, whether the weak should be more leniently treated than the strong, whether pardon should be granted on repentance, whether he who has been a Christian should profit by renunciation, whether profession of the name should be punished if there be no attendant crime or whether only the crimes associated with the name are subject to penalty. In the meantime I have taken the following course with those who were denounced to me as Christians. I asked them whether they were Christians. If they confessed, I asked a second and a third time with threat of penalty. If they persisted I ordered their execution, for I do not doubt that whatever it was that they profess, certainly their stubbornness and inflexible obstinacy deserved to be punished. There were others addicted to the same madness who, because they were Roman citizens, I sent to Rome. Soon after this incident, as usually happens when the crime spreads, a variety of cases appeared. An anonymous denunciation was laid before me containing many names. Those who denied that they were Christians or had been, who in my presence supplicated and placed incense and wine before your image, which I ordered placed among the statues of the gods, especially when they cursed Christ, which those who are really Christians cannot be brought to do, these I thought should be released. Some, denounced by an informer, at first said that they had been, but had ceased to be, some three years ago, some several years back and one even twenty years ago. These all worshiped your image and those of the gods and cursed Christ. They said that this was the sum of their fault or error, that they were accustomed at dawn on a stated day, to come together and sing a hymn to Christ as to a god, and that they mutually bound themselves on oath not in order to commit any crime but to refrain from theft, robbery, adultery, perjury or denial of trust funds. Then they disbanded and came together again to take food in common and quite harmless and this custom they had discontinued after my order in compliance with your mandate against forbidden societies."
The Emperor Trajan to Pliny
"You have followed the proper procedure in dealing with the Christians who were brought before you. No absolute rule can be laid down. They are not to be hunted out. If they are denounced and convicted, they are to be punished, but he who denies that he is a Christian and proves it by supplicating our gods, although suspect in the past, may gain pardon from penitence. Anonymous accusations are not to be entertained with respect to any crime. These are the worst examples of our age." From Bainton, Early Christianity, pp. 88-89.

Quadratus' one-sentence fragment from his "Apology" [this is all scholars have discovered]:
"But the works of our Savior were always present, for they were genuine: those that were healed, and those that were raised from the dead, who were seen not only when they were healed and when they were raised, but were also always present; and not merely while the Savior was on earth, but also after his death, they were alive for quite a while, so that some of them lived even to our day."

From Justin Martyr's "First Apology":
"Reason directs those who are truly pious and philosophical to honor and love only what is true, declining to follow traditional opinions, if these be worthless. For not only does sound reason direct us to refuse the guidance of those who did or taught anything wrong, but it is incumbent on the lover of truth, by all means, and if death be threatened, even before his own life, to choose to do and say what is right. Do you, then, since you are called pious and philosophers, guardians of justice and lovers of learning, give good heed, and hearken to my address; and if you are indeed such, it will be manifested. For we have come, not to flatter you by this writing, nor please you by our address, but to beg that you pass judgment, after an accurate and searching investigation, not flattered by prejudice or by a desire of pleasing superstitious men, nor induced by irrational impulse or evil rumors which have long been prevalent, to give a decision which will prove to be against yourselves. For as for us, we reckon that no evil can be done us, unless we be convicted as evil-doers or be proved to be wicked men; and you, you can kill, but not hurt us."

The Muratorian Fragment is the oldest known list of New Testament books. It was discovered by Ludovico Antonio Muratori in a manuscript in the Ambrosian Library in Milan, and published by him in 1740. * It is called a fragment because the beginning of it is missing. Although the manuscript in which it appears was copied during the seventh century, the list itself is dated to about 170 because its author refers to the episcopate of Pius I of Rome (died 157) as recent.
The Muratorian Fragment alludes to Matthew and Mark, although they are not mentioned because that part of the manuscript is missing.
NT books listed in Muratorian Fragment: Luke, John, Acts, Romans, I & II Corinthians, Galatians, Ephesians, Philippians, Colossians, I & II Thessalonians, I & II Timothy, Titus, Philemon, Jude, I & II John, and Revelation. It also included the Wisdom of Solomon.
NT books missing from Muratorian Fragment: Hebrews, James, I & II Peter, and III John.
Quote from the Muratorian Canon:
". . . at which nevertheless he was present, and so he placed [them in his narrative]. (2) The third book of the Gospel is that according to Luke. (3) Luke, the well-known physician, after the ascension of Christ, (4-5) when Paul had taken with him as one zealous for the law, (6) composed it in his own name, according to [the general] belief. Yet he himself had not (7) seen the Lord in the flesh; and therefore, as he was able to ascertain events, (8) so indeed he begins to tell the story from the birth of John. (9) The fourth of the Gospels is that of John, [one] of the disciples. (10) To his fellow disciples and bishops, who had been urging him [to write], (11) he said, 'Fast with me from today to three days, and what (12) will be revealed to each one (13) let us tell it to one another.' In the same night it was revealed (14) to Andrew, [one] of the apostles, (15-16) that John should write down all things in his own name while all of them should review it. And so, though various (17) elements may be taught in the individual books of the Gospels, (18) nevertheless this makes no difference to the faith of believers, since by the one sovereign Spirit all things (20) have been declared in all [the Gospels]: concerning the (21) nativity, concerning the passion, concerning the resurrection, (22) concerning life with his disciples, (23) and concerning his twofold coming; (24) the first in lowliness when he was despised, which has taken place, (25) the second glorious in royal power, (26) which is still in the future. What (27) marvel is it then, if John so consistently (28) mentions these particular points also in his Epistles, (29) saying about himself, 'What we have seen with our eyes (30) and heard with our ears and our hands (31) have handled, these things we have written to you? (32) For in this way he professes [himself] to be not only an eye-witness and hearer, (33) but also a writer of all the marvelous deeds of the Lord, in their order. (34) Moreover, the acts of all the apostles (35) were written in one book. For 'most excellent Theophilus' Luke compiled (36) the individual events that took place in his presence — (37) as he plainly shows by omitting the martyrdom of Peter (38) as well as the departure of Paul from the city [of Rome] (39) when he journeyed to Spain. As for the Epistles of (40-1) Paul, they themselves make clear to those desiring to understand, which ones [they are], from what place, or for what reason they were sent. (42) First of all, to the Corinthians, prohibiting their heretical schisms; (43) next, to the Galatians, against circumcision; (44-6) then to the Romans he wrote at length, explaining the order (or, plan) of the Scriptures, and also that Christ is their principle (or, main theme). It is necessary (47) for us to discuss these one by one, since the blessed (48) apostle Paul himself, following the example of his predecessor (49-50) John, writes by name to only seven churches in the following sequence: To the Corinthians (51) first, to the Ephesians second, to the Philippians third, (52) to the Colossians fourth, to the Galatians fifth, (53) to the Thessalonians sixth, to the Romans (54-5) seventh. It is true that he writes once more to the Corinthians and to the Thessalonians for the sake of admonition, (56-7) yet it is clearly recognizable that there is one Church spread throughout the whole extent of the earth. For John also in the (58) Apocalypse, though he writes to seven churches, (59-60) nevertheless speaks to all. [Paul also wrote] out of affection and love one to Philemon, one to Titus, and two to Timothy; and these are held sacred (62-3) in the esteem of the Church catholic for the regulation of ecclesiastical discipline. There is current also [an epistle] to (64) the Laodiceans, [and] another to the Alexandrians, [both] forged in Paul's (65) name to [further] the heresy of Marcion, and several others (66) which cannot be received into the catholic Church (67)— for it is not fitting that gall be mixed with honey. (68) Moreover, the epistle of Jude and two of the above-mentioned (or, bearing the name of) John are counted (or, used) in the catholic [Church]; and [the book of] Wisdom, (70) written by the friends of Solomon in his honour. (71) We receive only the apocalypses of John and Peter, (72) though some of us are not willing that the latter be read in church. (73) But Hermas wrote the Shepherd (74) very recently, in our times, in the city of Rome, (75) while bishop Pius, his brother, was occupying the [episcopal] chair (76) of the church of the city of Rome. (77) And therefore it ought indeed to be read; but (78) it cannot be read publicly to the people in church either among (79) the Prophets, whose number is complete, or among (80) the Apostles, for it is after [their] time. (81) But we accept nothing whatever of Arsinous or Valentinus or Miltiades, (82) who also composed (83) a new book of psalms for Marcion, (84-5) together with Basilides, the Asian founder of the Cataphrygians . . ." (This information gathered from http://www.bible-researcher.com/muratorian.html on 10 Dec 08)

A small quote from Celsius, as found in Origen: "The assertion made both by some of the Christians and by the Jews, the former saying that some God or son of God has come down to earth as judge of mankind, the latter saying he will come, is most shameful. . . . What is the purpose of such a descent on the part of God? . . . Was it in order to learn what was going on among men? . . . Does not He know everything? . . . If, then, He does know, why does He not correct men, and why can He not do this by His divine power? . . . Was He then unable to correct men merely by divine power, without sending some one specially endowed for the purpose? . . . Is it only now after such a long age that God has remembered to judge the life of men? Did He not care before? Either God really does change, as they say, into a mortal body; and it has already been said that this is an impossibility. Or He does not change, but makes those who see Him think that He does so, and leads them astray and tells lies."

Early development of Clergy from Irenaeus: "But inasmuch as it would be very tedious in a book such as this to rehearse the lines of succession in every church, we will put to confusion all persons who, whether from waywardness or vainglory or blindness or perversity of mind, combine wrongfully together in any way, by pointing to the tradition, derived from the apostles, of that great and illustrious church founded and organized at Rome by the two glorious apostles, Peter and Paul, and to the faith declared to mankind and handed down to our own time through its bishops in their succession. For unto this church [in Rome], on account of its commanding position, every church, that is to say, the faithful from everywhere, must needs resort and in it the tradition that comes from the apostles has been continuously preserved by those who are from everywhere." After this, Irenaeus lists the Bishops of Rome from Peter to his time: Linus, Anacletus, Clement, Evaristus, Alexander, Sixtus, Telesphorus, Hyginus, Pius, Anicetus, Soter, and Eleutherus, who was Bishop of Rome at the writing of "Against Heresies."

Early form of Creed: "The Church, though dispersed throughout the whole world, even to the ends of the earth, has received from the apostles and their disciples this faith:
in one God, the Father Almighty, Maker of heaven, and earth, and the sea, and all things that are in them;
and in one Christ Jesus, the Son of God, who became incarnate for our salvation;
and in the Holy Spirit, who proclaimed through the prophets the dispensations of God,
and the advents,
and the birth from a virgin,
and the passion,
and the resurrection from the dead,
and the ascension into heaven in the flesh of the beloved Christ Jesus, our Lord,
and his [future] manifestation from heaven in the glory of the Father 'to gather all things in one,' and to raise up anew all flesh of the whole human race, in order that to Christ Jesus, our Lord, and God, and Savior, and King, according to the will of the invisible Father, 'every knee should bow, of things in heaven, and things in earth, and things under the earth, and that every tongue should confess' to Him,
and that He should execute just judgment towards all; that He may send 'spiritual wickednesses,' and the angels who transgressed and became apostates, together with the ungodly, and unrighteous, and the wicked, and profane among men, into everlasting fire;
but may, in the exercise of His grace, confer immortality on the righteous, and holy, and those who have kept His commandments, and have persevered in His love, some from the beginning [of their Christian course], and others from [the date of] their repentance, and may surround them with everlasting glory." From http://www.ccel.org/ccel/schaff/anf01.ix.ii.xi.html, Irenaeus "Against Heresies" 10:1.

The Old Roman Symbol:
I believe in God the Father almighty;
And in Jesus Christ His only Son, our Lord;
Who was born of the Holy Spirit and the Virgin Mary;
Crucified under Pontius Pilate and buried;
The third day rose again from the dead;
He ascended into heaven,
And sits at the right hand of the Father;
From where he shall come to judge the quick [living] and the dead.
In the Holy Spirit;
The holy Church;
The forgiveness of sins;
The resurrection of the body.

Quote from Tertullian about baptism:
And so, according to the circumstances and disposition, and even age, of each individual, the delay of baptism is preferable; principally, however, in the case of little children.
From http://www.ccel.org/ccel/schaff/anf03.vi.iii.xviii.html.

Quote from a Roman Certificate certifying one has sacrificed to the gods, c.250
To the superintendents of offerings and sacrifices at the city from Aurelius . . . the son of Theodorus and Pantonymis, of the said city. It has ever been my custom to make sacrifices and libations to the gods, and now also I have in your presence in accordance with the command poured libations and sacrificed and tasted the offerings together with my son Aurelius Dioscorus and my daughter Aurelia Lais. I, therefore, request you to certify my statement.

Quote from Cyprian defending those who waivered under persecution and sacrificed to the emperor:
But (say they) subsequently tortures had come and severe sufferings were threatening those who resisted. He may complain of tortures who has been overcome by tortures; he may offer the excuse of suffering who has been vanquished in suffering. Such a one may ask, and say, “I wished indeed to strive bravely, and, remembering my oath, I took up the arms of devotion and faith; but as I was struggling in the encounter, varied tortures and long-continued sufferings overcame me. My mind stood firm, and my faith was strong, and my soul struggled long, unshaken with the torturing pains; but when, with the renewed barbarity of the most cruel judge, wearied out as I was, the scourges were now tearing me, the clubs bruised me, the rack strained me, the claw dug into me, the fire roasted me; my flesh deserted e in the struggle, the weakness of my bodily frame gave way,--not my mind, but my body, yielded in the suffering.” Such a plea may readily avail to forgiveness.
But (say they) subsequently tortures had come and severe sufferings were threatening those who resisted. He may complain of tortures who has been overcome by tortures; he may offer the excuse of suffering who has been vanquished in suffering. Such a one may ask, and say, “I wished indeed to strive bravely, and, remembering my oath, I took up the arms of devotion and faith; but as I was struggling in the encounter, varied tortures and long-continued sufferings overcame me. My mind stood firm, and my faith was strong, and my soul struggled long, unshaken with the torturing pains; but when, with the renewed barbarity of the most cruel judge, wearied out as I was, the scourges were now tearing me, the clubs bruised me, the rack strained me, the claw dug into me, the fire roasted me; my flesh deserted e in the struggle, the weakness of my bodily frame gave way,--not my mind, but my body, yielded in the suffering.” Such a plea may readily avail to forgiveness.

Nicene Creed of 325:
We believe in one God, the Father Almighty, Maker of all things visible and invisible.
And in One Lord Jesus Christ, the Son of God, begotten of the Father, the only-begotten; that is, of the essence of the Father, God of God, Light of Light, very God of very God, begotten, not made, being of one substance with the Father, by whom all things were made both in heaven and on earth; who for us men, and for our salvation, came down and was incarnate and was made man; he suffered, and the third day he rose again, ascended into heaven; from where he shall come to judge the quick and the dead.
And in the Holy Spirit.
But those who say: “There was a time when he was not,” and “He was not before he was made;” and “He was made out of nothing,” or “He is of another substance” or “essence,” or “The Son of God is created,” or “changeable,” or “alterable”--they are condemned by the holy catholic [meaning “universal” and not the Roman Catholic Church] and apostolic Church.
See http://www.earlychurchtexts.com/public/creed_of_nicaea_325.htm

Portion of Athanasius' 39th Festal (annual) letter of AD 367 concerning the 27 books of the New Testament:
These are, the four Gospels, according to Matthew, Mark, Luke, and John. Afterwards, the Acts of the Apostles and Epistles (called Catholic), seven, viz. of James, one; of Peter, two; of John, three; after these, one of Jude. In addition, there are fourteen Epistles of Paul, written in this order. The first, to the Romans; then two to the Corinthians; after these, to the Galatians; next, to the Ephesians; then to the Philippians; then to the Colossians; after these, two to the Thessalonians, and that to the Hebrews; and again, two to Timothy; one to Titus; an lastly, that to Philemon. And besides, the Revelation of John.
These are fountains of salvation, that they who thirst may be satisfied with the living words they contain, In these alone is proclaimed the doctrine of godliness. Let no man add the these, neither let him take ought from these.

Proclamation declaring Christianity the official religion of the Roman Empire by Emperor Theodosius I:
It is our desire that all the various nations which are subject to our clemency and moderation, should continue to the profession of that religion which was delivered to the Romans by the divine Apostle Peter, as it has been preserved by faithful tradition and which is now professed by the Pontiff Damasus and by Peter, Bishop of Alexandria, a man of apostolic holiness. According to the apostolic teaching and the doctrine of the Gospel, let us believe the one deity of the Father, the Son and the Holy Spirit, in equal majesty and in a holy Trinity. We authorize the followers of this law to assume the title of Catholic Christians; but as for the others, since, in our judgment they are foolish madmen, we decree that they shall be branded with the ignominious name of heretics, and shall not presume to give to their conventicles the name of churches. They will suffer in the first place the chastisement of the divine condemnation and in the second the punishment of our authority which in accordance with the will of Heaven shall decide to inflict.

The Creed which came out of the Council of Constantinople:
We believe in one God, the Father Almighty, Maker of heaven and earth, and of all things visible and invisible.
And in one Lord Jesus Christ, the only-begotten Son of God, begotten of the Father before all worlds, Light of Light, very (or true) God of very (or true) God, begotten, not made, being of one substance with the Father; by whom all things were made; who for us men, and for our salvation, came down from heaven, and was incarnate by the Holy Ghost of the Virgin Mary, and was made man; he was crucified for us under Pontius Pilate, and suffered, and was buried, and the third day he rose again, according to the Scriptures, and ascended into heaven, and sits on the right hand of the Father; from where he shall come again, with glory, to judge the quick (living) and the dead; whose kingdom shall have no end.
And in the Holy Ghost, the Lord and Giver of life, who proceeds from the Father, who with the Father and the Son together is worshiped and glorified, who spake by the prophets.
In one holy catholic [meaning “universal” and apostolic Church;
we acknowledge one baptism for the remission of sins;
we look for the resurrection of the dead, and the life of the world to come. Amen.