Epistle of Magnetes to Diogenetus(Edit)

This is one of the earliest examples of Christian apologetics dating from the mid to late second century.

"But as to their scrupulosity concerning meats, and their superstition as respects the Sabbaths, and their boasting about circumcision, and their fancies about fasting and the new moons, which are utterly ridiculous and unworthy of notice -- I do not think that you require to learn anything from me. For, to accept some of those things which have been formed by God for the use of men as properly formed, and to reject others as useless and redundant -- how can this be lawful? And to speak falsely of God, as if He forbade us to do what is good on the Sabbath-days -- how is not this impious? And to glory in the circumcision of the flesh as a proof of election, and as if, on account of it, they were specially beloved by God -- how is it not a subject of ridicule? And as to their observing months and days, (c.f. Galatians 4:10) as if waiting upon the stars and the moon, and their distributing, according to their own tendencies, the appointments of God, and the vicissitudes of the seasons, some for festivities, and others for mourning -- who would deem this a part of divine worship, and not much rather a manifestation of folly?"

Letter LXXVI from Ambrose to Iranaeus(Edit)

For the strife which before existed in the flesh being removed, an universal peace has been made in heaven; that men might be like Angels upon earth, that the Gentiles and Jews might be made one, that both the new and old man might be united, the middle wall of partition, which, as a hostile barrier, had once divided them, being broken down. For the nature of our flesh having stirred up anger discord and dissension, and the law having bound us with the chains of condemnation, Christ Jesus subdued by mortification the wantonness and intemperance of the flesh, and made void the law of commandment contained in ordinances, declaring thereby that the decrees of the spiritual Law are not to be interpreted according to the letter; putting an end to the slothful rest of the Sabbath and to the superfluous rite of outward circumcision, and opening to all access by one Spirit unto the Father. For how can there be any discord, where there is one calling, one body and one spirit?

Bishop Ambrose of Milan (4th century)(Edit)

In a letter written by a catechumen of Ambrose regarding his question to Ambrose of the Sabbath:

"To My Brother and Fellow-Presbyter Casulanus, Most Beloved and Longed For, Augustin Sends Greeting in the Lord.

"31. The next day is the Jewish Sabbath, on which day Christ's body rested in the grave, as in the original fashioning of the world God rested on that day from all His works. Hence originated that variety in the robe of His bride which we are now considering: some, especially the Eastern communities, preferring to take food on that day, that their action might be emblematic of the divine rest; others, namely the Church of Rome, and some churches in the West, preferring to fast on that day because of the humiliation of the Lord in death. Once in the year, namely at Easter, all Christians observe the seventh day of the week by fasting, in memory of the mourning with which the disciples, as men bereaved, lamented the death of the Lord (and this is done with the utmost devoutness by those who take food on the seventh day throughout the rest of the year); thus providing a symbolical representation of both events,-of the disciples' sorrow on one seventh day in the year, and of the blessing of repose on all the others. There are two things which make the happiness of the just and the end of all their misery to be confidently expected, viz. death and the resurrection of the dead. In death is that rest of which the prophet speaks: "Come, my people, enter thou into thy chambers, and shut thy doors about thee: hide thyself as it were for a little moment, until the indignation be overpast." In resurrection blessedness is consummated in the whole man, both body and soul. Hence it came to be thought that both of these things death and resurrection should be symbolized, not by the hardship of fasting, but rather by the cheerfulness of refreshment with food, excepting only the Easter Saturday, on which, as I have said, it had been resolved to commemorate by a more protracted fast the mourning of the disciples, as one of the events to be had in remembrance.

Chap. XIV.

"32. Since, therefore (as I have said above), we do not find in the Gospels or in the apostolical writings, belonging properly to the revelation of the New Testament, that any law was laid down as to fasts to be observed on particular days; and since this is consequently one of many things, difficult to enumerate, which make up a variety in the robe of the King's daughter, that is to say, of the Church,-I will tell you the answer given to my questions on this subject by the venerable Ambrose Bishop of Milan, by whom I was baptized. When my mother was with me in that city, I, as being only a catechumen, felt no concern about these questions; but it was to her a question causing anxiety, whether she ought, after the custom of our own town, to fast on the Saturday, or, after the custom of the Church of Milan, not to fast. To deliver her from perplexity, I put the question to the man of God whom I have just named. He answered, "What else can I recommend to others than what I do myself?" When I thought that by this he intended simply to prescribe to us that we should take food on Saturdays-for I knew this to be his own practice-he, following me, added these words: "When I am here I do not fast on Saturday; but when I am at Rome I do: whatever church you may come to, conform to its custom, if you would avoid either receiving or giving offence." This reply I reported to my mother, and it satisfied her, so that she scrupled not to comply with it; and I have myself followed the same rule. Since, however, it happens, especially in Africa, that one church, or the churches within the same district, may have some members who fast and others who do not fast on the seventh day, it seems to me best to adopt in each congregation the custom of those to whom authority in its government has been committed. Wherefore, if you are quite willing to follow my advice, especially because in regard to this matter I have spoken at greater length than was necessary, do not in this resist your own bishop, but follow his practice without scruple or debate."

Pliny's Letter to Trajan(Edit)

Pliny the Younger was governor of Pontus/Bithynia from 111-113 AD. We have a whole set of exchanges of his letters with the emperor Trajan on a variety of administrative political matters. These two letters are the most famous, in which P. encounters Christianity for the first time.

"They asserted, however, that the sum and substance of their fault or error had been that they were accustomed to meet on a fixed day before dawn and sing responsively a hymn to Christ as to a god, and to bind themselves by oath, not to some crime, but not to commit fraud, theft, or adultery, not falsify their trust, nor to refuse to return a trust when called upon to do so. When this was over, it was their custom to depart and to assemble again to partake of food--but ordinary and innocent food. Even this, they affirmed, they had ceased to do after my edict by which, in accordance with your instructions, I had forbidden political associations. Accordingly, I judged it all the more necessary to find out what the truth was by torturing two female slaves who were called deaconesses. But I discovered nothing else but depraved, excessive superstition."

Acts 20:7(Edit)

"On the first day of the week, when we were gathered together to break bread, Paul talked with them, intending to depart on the next day, and he prolonged his speech until midnight."

(This one is particularly telling, given the numerous instances of the Apostles attending the synagogue and otherwise observing the Sabbath.)

Epistle of Barnabas 15:8-9(Edit)

An epistle written sometime between 70AD and 132AD attributed to somebody named Barnabas.

Finally He saith to them; Your new moons and your Sabbaths I cannot away with. Ye see what is His meaning ; it is not your present Sabbaths that are acceptable unto Me, but the Sabbath which I have made, in the which, when I have set all things at rest, I will make the beginning of the eighth day which is the beginning of another world. Wherefore also we keep the eighth day for rejoicing, in the which also Jesus rose from the dead, and having been manifested ascended into the heavens.

The Teachings of the Apostles (The Didache)(Edit)

The Didache is a late first to early second century writing that was widely circulated in the early church. It is one of the earliest examples of a catechism and was considered by some in the early church to be scripture. It was ultimately not included because of its lack of apostolic origin, although its orthodoxy was never questioned.

"And on the Lord's own day gather yourselves together and break bread and give thanks, first confessing your transgressions, that your sacrifice may be pure..." Didache 14:1

Dionyius's Letter to Rome(Edit)

Dionyius was bishop of Corinth in the early second century. Fragments of his letter to the Roman church is preserved by Eusebius in his book on Church History.

"We passed this holy Lord's day, in which we read your letter, from the constant reading of which we shall be able to draw admonition, even as from the reading of the former one you sent us written through Clement."

Bardaisan's Laws of Various Countries(Edit)

Bardaisan/Bardesanes (154-222 A.D.), http://en.wikipedia.org/wiki/Bardaisan - a second century Gnostic Christian who although he was a part of a school of unorthodox teachings, sheds some light into some of the more uncontroversial aspects of Christianity of that era.

"And what shall we say of the new race of us Christians, whom Christ at His advent planted in every country and in every region? For, lo! Wherever we are, we are all called after the one name of Christ -- Christians. On one day, the first of the week, we assemble ourselves together, and on the days of the readings we abstain from taking sustenance."

Clement of Alexandria's Stromata(Edit)

Clement of Alexandra (150-215AD) was a theologian who although was criticized by some later writers is still highly regarded as a Church Father and is appreciated for his insight into Christianity of the second century and early third century.

Stromata Book VII Chapter XII:

"He, in fulfilment of the precept, according to the Gospel, keeps the Lord's day, when he abandons an evil disposition, and assumes that of the Gnostic, glorifying the Lord's resurrection in himself."

Cyprian of Carthage's Epistle 58(Edit)

Cyprian was the bishop of Carthage during the middle of the third century. Cyprian famoudly disagreed vehemently with Stephen the Roman bishop on some matters surrounding baptism and the lapsi to which Stephen called Cyprian 'antichrist'.

"For because the eighth day, that is, the first day after the Sabbath, was to be that on which the Lord should rise again, and should quicken us, and give us circumcision of the spirit, the eighth day, that is, the first day after the Sabbath, and the Lord's day, went before in the figure; which figure ceased when by and by the truth came, and spiritual circumcision was given to us."

Ignatius's Letter to the Magnesians(Edit)

Ignatius (~35-108AD), bishop of Antioch, Paul's home church and appointed by John, in writing to the Magnesians in chapter 9 describes that even the converted Jews observe Sunday.

http://www.ccel.org/ccel/schaff/anf01.v.iii.ix.html

"Be not deceived with strange doctrines, nor with old fables, which are unprofitable. For if we still live according to the Jewish law, we acknowledge that we have not received grace...

"Those who were brought up in the ancient order of things have come to the possession of a new hope, no longer observing the Sabbath, but living in the observance of the Lord's Day, on which also our life has sprung up again by Him and by His death...

"It is absurd to profess Christ Jesus, and to Judaize. For Christianity did not embrace Judaism, but Judaism Christianity, that so every tongue which believes might be gathered together to God."

Ignatius' Letter to the Philadelphians 6:1 - "But if any one preach the Jewish law unto you, listen not to him."

Justin Martyr's First Apology(Edit)

Justin Martyr (100-165AD) is a famous early second century apologist whose various writings to Romans and Jews shed light on how Christianity contrasted with those two groups. He was later martyred by Rome.

http://www.ccel.org/ccel/schaff/anf01.v.iii.ix.html

And on the day called Sunday, all who live in cities or in the country gather together to one place, and the memoirs of the apostles or the writings of the prophets are read, as long as time permits; then, when the reader has ceased, the president verbally instructs, and exhorts to the imitation of these good things. Then we all rise together and pray, and, as we before said, when our prayer is ended, bread and wine and water are brought, and the president in like manner offers prayers and thanksgivings, according to his ability, and the people assent, saying Amen; and there is a distribution to each, and a participation of that over which thanks have been given, and to those who are absent a portion is sent by the deacons. And they who are well to do, and willing, give what each thinks fit; and what is collected is deposited with the president, who succours the orphans and widows and those who, through sickness or any other cause, are in want, and those who are in bonds and the strangers sojourning among us, and in a word takes care of all who are in need. But Sunday is the day on which we all hold our common assembly, because it is the first day on which God, having wrought a change in the darkness and matter, made the world; and Jesus Christ our Saviour on the same day rose from the dead. For He was crucified on the day before that of Saturn (Saturday); and on the day after that of Saturn, which is the day of the Sun, having appeared to His apostles and disciples, He taught them these things, which we have submitted to you also for your consideration.

Justin Martry's Dialogue with Trypho the Jew(Edit)

This is one of Justin's more famous writings. It is an alleged discussion between Justin and a Jewish man named Trypho discussing why Justin became Christian and why Christianity is the new covenant that supersedes the old covenant of Judaism.

At one point, Trypho explains the Jewish way to be accepted by God:

"First be circumcised, then observe what ordinances have been enacted with respect to the Sabbath, and the feasts, and the new moons of God; and, in a word, do all things which have been written in the law; and then perhaps you shall obtain mercy from God.... To keep the Sabbath, to be circumcised, to observe months, and to be washed if you touch anything prohibited by Moses, or after sexual intercourse..."

Trypho continues his criticism:

"You, professing to be pious, and supposing yourselves better than others, are not in any particular separated from them, and do not alter your mode of living from other nations, in that you observe no festivals or sabbaths and do not have the rite of circumcision.... Yet you expect to obtain some good thing from God, while you do not obey His commandments. Have you not read, that that soul shall be cut off from his people who shall not have been circumcised on the eighth day?"

And Justin replied that Christians were indeed obedient to God, even when obedience was extremely painful:

"We too would observe the fleshly circumcision, and the Sabbaths, and in short all the feasts, if we did not know for what reason they were enjoined you, -- namely, on account of your transgressions and the hardness of your hearts. For if we patiently endure all things contrived against us by wicked men...even as the new Lawgiver commanded us: how is it, Trypho, that we would not observe those rites which do not harm us, -- I speak of fleshly circumcision, and Sabbaths and feasts?"

Justin explained the reason Christians ignored the Jewish laws:

"We live not after the law, and are not circumcised in the flesh as your forefathers were, and do not observe sabbaths as you do.... An eternal and final law -- namely, Christ -- has been given to us.... He is the new law, and the new covenant.... The new law requires you to keep perpetual sabbath, and you, because you are idle for one day, suppose you are pious, not discerning why this has been commanded you.... If there is any perjured person or a thief among you, let him cease to be so; if any adulterer, let him repent; then he has kept the sweet and true sabbaths of God."

Tertullian's Apology(Edit)

Tertullian (160-225AD) - http://en.wikipedia.org/wiki/Tertullian - 3rd century church father who wrote extensively from Carthage. Towards the end of his life he became disillusioned with what he saw was corruption creeping in the church and joined the Montanists, but many of his earlier writings are still foundational in the study of the early church.

"These send us to the religion of Persia, though we are far from adoring a painted sun, like them who carry about his image everywhere upon their bucklers. This suspicion took its rise from hence, because it was observed that Christians prayed with their faces towards the east. But some of you likewise out of an affectation of adoring some of the celestial bodies wag your lips towards the rising sun; but if we, like them, celebrate Sunday as a festival and day of rejoicing, it is for a reason vastly distant from that of worshipping the sun; for we solemnize the day after Saturday in contradistinction to those who call this day their Sabbath, and devote it to ease and eating, deviating from the old Jewish customs, which they are now very ignorant of." - Chapter XVI