In the first centuries A.D. the cycle of Christian time grew out of the conviction that all-time finds its meaning in the death and resurrection of Christ. Thus the early Christians, beginning with the paschal event, extended the Christian calendar forward to Pentecost and backward to Lent and Holy Week. Later, in the fourth century, Advent, Christmas, and Epiphany were developed to complete the cycle.
The Easter Cycle
In the first days of the life of the church following Pentecost, there is no indication of any observance of special times. However, it is clear that by the time of Paul’s ministry it had become customary for local communities to gather for the breaking of bread on the first day of the week, and it has been suggested that occurred after sundown ending the Sabbath (see Acts 20:7–12). By the end of the first century, the observance of the first day by common worship seems established, as was the observance of the fourth and sixth days of the week with fasting (see Didache, chaps. 1 and 14.) For most of the church, this shaping of the week sufficed, and one week was like every other. The Gentile church had no reason to adopt the major annual festivals of Judaism. However, it seems likely that the community in Jerusalem continued to observe Passover, with its day of preparation a memorial of the death of Jesus. This community was largely dispersed following the destruction of the city by Titus, and our earliest evidence for the annual observance of Passover by Christians comes from Asia Minor. For example in the Epistula Apostolorum, 15, a document assigned to Asia Minor in the second century (perhaps the first half of the century), the risen Christ is presented as addressing the apostles in the following words:
And you, therefore, celebrate the remembrance of my death, i.e., the Passover; then will one of you be thrown into prison for my name’s sake, and he will be very grieved and sorrowful, for while you celebrate the Passover, he who is in custody did not celebrate it with you. And I will send my power in the form of my angel, and the door of the prison will open, and he will come out and come to you to watch with you and to rest. And when you complete my Agape and my remembrance at the crowing of the cock, he will again be taken and thrown in prison for a testimony, until he comes out to preach, as I have commanded you.
In Asia Minor, the preparation of the Passover (the fourteenth day of the first spring month, Nisan) was observed with fasting, and a vigil was kept through the night of Jewish feasting until cockcrow when the observance was ended with a simple Eucharist. When it became difficult to observe the day according to the Jewish calendar, which was adjusted as needed by rabbinical authorities, some Christians in Asia Minor adopted the local version of the Julian calendar and kept their Passover on the fourteenth day of its first spring month, Artemisios. When the capital of the empire moved to Constantinople in the fourth century, the Roman calendar was adopted in Asia Minor, and we encounter its designation of 14 Artemisios, April 6, as a fixed date associated with Pascha (the Aramaic word for Passover adopted by Christians). By the third century in the West, on the other hand, the historical date of the Lord’s death had been computed to have been March 25.
The emperor Hadrian rebuilt Jerusalem in 132, and all the circumcised, including Christians, were forbidden to enter the new city, Aelia, built upon the rubble of the old. With the expulsion of Jewish Christians, Gentile bishops came to assume leadership of the Jerusalem church. It is believed that it was this mixing of Gentile leadership with local Jewish Christian custom that led to the observance of the paschal fast on Sabbath and the vigil through the night from Sabbath to the Lord’s Day, with the concluding Eucharist in the early hours of Sunday morning, in accordance with prevailing Gentile custom. So the annual Passover became Easter Sunday. For many in the second century, the annual paschal fast on Sabbath was joined to the weekly fast on Friday to yield a two-day fast, and in the following century, both Syria and Egypt yield evidence of the further extension of the paschal fast to six days, the “Holy Week” still known to us.
In the second century, we encounter significant evidence that the celebration of our Lord’s triumph, begun with the Eucharist that terminated the paschal fast, was extended for fifty days, called the Pentecost. This was probably derivative from the counting of fifty days to the Feast of Weeks in Judaism, but it took on a distinctive Christian character as a period of rejoicing during which fasting and kneeling in prayer were considered inappropriate. During the third century this period, but especially Pascha itself, came to be considered the most appropriate time for baptism, and in some churches, the immediately preceding weeks were devoted to the preparation of candidates for that rite. After the Council of Nicea (A.D. 325) that period was extended to the forty days we know as Lent.
The Christmas Cycle
The date of our Lord’s birth is not known, and the Gospels are clearly indifferent to the question. Mark, indeed, does not mention the Nativity and is content to present the baptism in Jordan as the beginning of the gospel. Around the turn of the second to the third century, Clement of Alexandria reports that some Basilideans celebrated the baptism on January 6, and there is reason to believe that he associated this same date with the birth of Jesus. This would be just nine months after the paschal date of April 6, and some of the early paschal homilies in Asia Minor speak not only of the Lord’s passion and resurrection but also of the Incarnation and so of the conception in the womb of the virgin. By the fourth century, we know that the date of the Lord’s death had been taken to be that of the conception as well, allowing the setting of the Nativity date nine months later. As January 6 appeared in the East as that nativity date, so by the early fourth century (or earlier) December 25 was recognized as the nativity date in the West. That was also the date of a pagan festival, the Birthday of the Invincible Sun, instituted by the emperor Aurelian in A.D. 274. The relationship between the new Roman festival and the Christian association of the birth of the Lord with the same date remains disputed. Some believe that Christians chose the date already celebrated and recast it as the birthday of the Sun of Righteousness. Others suppose the Christian date to have been arrived at independently by computation from March 25, established as the date of the Lord’s death (and conception?) long before Aurelian’s festival.
In the course of the fourth century, the two festivals of the Nativity of Christ (December 25) and the Epiphany (January 6) were mutually adopted in East and West. In the East, Epiphany celebrated both Christ’s birth and baptism in the Jordan. In the West, however, the Matthean nativity narrative was divided, and the January 6 festival celebrated the visit of the Magi, leading to the restricted understanding of Epiphany as “the manifestation of Christ to the Gentiles.”
Not until the sixth century did there appear the fast before Christmas, a fast of forty days progressively shortened at Rome to the four Sundays of Advent, which we now know as the opening season of the Christian year.