In the Judeo-Christian Scriptures, in Genesis, the seven-day week is defined after the description of God's efforts in establishing the world, and universe with the seventh day being the Sabbath, commemorating God's day of rest. In Apostolic times the practice is noted in Acts of meeting together on the first day of the week for Eucharistic Sacrifice which is called the Lord's Day in remembrance of our Lord's Resurrection. By the second century the Lord's Day was looked upon as the day of rest and the day for celebrating the Divine Liturgy, replacing the Jewish Sabbath. Then in 325, the Council of Nicea formally declared that the Lord's Day, Sunday, was the day of worship for Orthodox Christians.
Naming of the days of the week began when the Romans adopted the seven-day week from Egypt during the early centuries of the Christian era using names from the then-known planets. When the Germanic peoples adopted the seven-day week from the Romans, they applied the names of the Teutonic deities to the days of the week. These Roman and Teutonic names have continued to be used today except that in some languages the first day has been renamed for the Lord's Day or the Resurrection while the seventh day may be called the Sabbath.
In a large part of the world, the civil calendars have been altered, making Monday the first day of the week, thus placing Sunday as the seventh day.
The practice of observing the Divine Liturgy on the first day of the week has its origin in Apostolic times. Then, the first day of the week was a day of special observance for the Christian community as it assembled to celebrate the breaking of the bread as indicated in Acts 20:7 and I Cor 16:2. Later, the Didache of the first or second century gives the injunction: "On the Lord's Day come together and break bread. And give thanks, after confessing your sins that your sacrifice may be pure." The Christian writers St Justin Martyr and Tertullian of the third century mention assembling for worship on the first day of the week. By the fourth century the practice of the earlier times of setting aside first day of the week for assembly and rest began to be codified in both civil and church canons and specifically for the Orthodox Church in the canons of the Council of Nicea.
The Sabbath day is the seventh day, it is the day of rest in this world, the final day of the week. The next day, Sunday, is symbolic of the first day of creation, but also the last day of the Kingdom of God, the eighth day. The first day is also the eighth day, the day beyond the confines of this world, the day which stands for the life of the world to come, the day of the eternal rest of the Kingdom of God.
The number eight has symbolical significance in both Jewish and Christian spiritual tradition in that it signifies more than completion and fullness. Eight signifies the Kingdom of God and the life of the world to come, seven being the number of earthly time.
For Orthodox Christians, Sunday is the day of Christ's resurrection from the dead, the day of God's judgment and victory predicted by the prophets. Sunday inaugurates the presence and the power of the "kingdom to come", already within the life of this present world. It is a weekly celebration of Pascha.
Liturgically, the Lord's Day begins at sunset of Saturday, with the vespers service. Many priests hear Confessions after this service for the faithful who are preparing for the Holy Communion in the morning. They also fast, usually starting at midnight.
Before the Divine Liturgy, of Sunday morning, many parishes have the Matins service, some just read the Hours.
The Divine Liturgy is always celebrated on Sunday morning before noon. Because of the resurrectional theme of the day, the faithful do not kneel at the Liturgy on Sundays. Litanies for the dead, memorial services, and blessing of graves were historically not permitted on this day, but in practices, it is now common.
Each Sunday the has one of the eight tones:
Troparion of the Resurrection (Tone 1)
- When the stone had been sealed by the Jews, and the soldiers where guarding Thine immaculate Body,
- Thou didst rise on the third day, O Savior, granting life unto the world.
- Wherefore, the Hosts of the Heavens cried out to Thee, O Life-giver: Glory to Thy Resurrection, O Christ.
- Glory to Thy kingdom. Glory to Thy dispensation, O only Lover of mankind.
Kontakion of the Resurrection (Tone 1)
- As God Thou didst arise from the tomb in glory,
- and Thou didst raise the world together with Thyself.
- And mortal nature praiseth Thee as God, and death hath vanished.
- And Adam danceth, O Master, and Eve, now freed from fetters, rejoiceth as she crieth out:
- Thou art He, O Christ, that grantest unto all resurrection.
Troparion of the Resurrection (Tone 2).
- When Thou didst descend unto death, O Life Immortal,
- then didst Thou slay Hades with the lightning of Thy Divinity.
- And when Thou didst also raise the dead out of the nethermost depths, all the Hosts of Heavens cried out:
- O Lifegiver, Christ our God, glory be to Thee.
Kontakion of the Resurrection (Tone 2) .
- Thou didst arise from the tomb, O omnipotent Savior,
- and Hades was terrified on beholding the wonder;
- and the dead arose, and creation at the sight thereof rejoiceth with Thee.
- And Adam also is joyful, and world, O my Savior, praiseth Thee for ever.
Troparion of the Resurrection (Tone 3)
- Let the heavens be glad; let earthly things rejoice;
- for the Lord hath wrought might with His arm.
- He hath trampled down death by death; the first-born of the dead hath He become.
- From the belly of Hades hath He delivered us
- and hath granted to the world great mercy.
Kontakion of the Resurrection (Tone 3) .
- Thou didst rise today from the tomb, O Merciful One,
- and didst lead us out of the gates of death.
- Today Adam danceth and Eve rejoiceth;
- and together with them both the Prophets and Patriarchs unceasingly praise the divine might of Thine authority.
Troparion of the Resurrection (Tone 4)
- Having learned the joyful proclamation of the Resurrection from the angel,
- and having cast off the ancestral condemnation,
- the women disciples of the Lord spake to the apostles exultantly:
- Death is despoiled and Christ God is risen, granting to the world great mercy.
Kontakion of of the Resurrection (Tone 4) .
- My Savior and Redeemer hath, as God,
- raised up the earthborn from the grave and from their fetters,
- and He hath broken the gates of Hades, and, Master, hath risen on the third day.
Troparion of the Resurrection (Tone 5) .
- Let us, O faithful, praise and worship the Word
- Who is co-unorignate with the Father and the Spirit, and Who was born of the Virgin for our salvation;
- for He was pleased to ascend the Cross in the flesh and to endure death,
- and to raise the dead by His glorious Resurrection
Kontakion of the Resurrection (Tone 5) .
- Unto Hades, O my Savior, didst Thou descend, and having broken its gates as One omnipotent,
- Thou, as Creator, didst raise up the dead together with Thyself.
- And Thou didst break the sting of death, and didst deliver Adam from the curse,
- O Lover of mankind.
- Wherefore, we all cry unto Thee: Save us, O Lord.
Troparion of the Resurrection (Tone 6) .
- Angelic Hosts were above Thy tomb, and they that guarded Thee became as dead.
- And Mary stood by the grave seeking Thine immaculate Body.
- Thou didst despoil Hades and wast not tempted by it. Thou didst meet the Virgin and didst grant us life.
- O Thou Who didst rise from the dead, O Lord, glory be to Thee.
Kontakion of the Resurrection (Tone 6) .
- Having by His life-bestowing hand raised up all the dead out of the dark abysses,
- Christ God, the Giver of Life, hath bestowed the Resurrection upon the fallen human race;
- for He is the Savior of all, the Resurrection,
- and the Life, and the God of all.
Troparion of the Resurrection (Tone 7) .
- Thou didst destroy death by Thy Cross, Thou didst open Paradise to the thief.
- Thou didst change the lamentation of the Myrrh-bearers,
- and Thou didst command Thine Apostles to proclaim that Thou didst arise,
- O Christ God, and grantest to the world great mercy.
Kontakion of the Resurrection (Tone 7) .
- No longer will the dominion of death be able to keep men captive;
- for Christ hath descended, demolishing and destroying the powers thereof.
- Hades is bound; the Prophets rejoice with one voice, saying:
- A Savior hath come for them that have faith. Come forth,
- ye faithful, for the Resurrection.
Troparion of the Resurrection (Tone 8) .
- From on high didst Thou descend, O Compassionate One;
- to burial of three days hast Thou submitted that Thou mightest free us from our passions.
- O our Life and Resurrection, O Lord, glory be to Thee.
Kontakion of the Resurrection (Tone 8)
- Having arisen from the tomb,
- Thou didst raise up the dead and didst resurrect Adam.
- Eve also danceth at Thy Resurrection, and the ends of the world celebrate Thine arising from the dead,
- O Greatly-merciful One.
- "Orthodox Worship" (cf. "Beginning the day and the week") by Rev. Alciviadis C. Calivas, Th.D. (GOARCH)
- Questions & Answers (cf. Question 3) (GOARCH)
- Q & A About Orthodoxy by Fr. John Matusiak (OCA)
- Post-Easter Sundays from The Orthodox Faith by Fr. Thomas Hopko (OCA)
- Sunday: Catholic Encyclopedia