The Lord's Day

Introduction: Why Sunday?

Every week, Christians around the world gather for worship on Sunday—the first day of the week. This practice is so universal and so ancient that most Christians never question it. But the questions are worth asking: Why Sunday and not Saturday? Is the Christian Sunday a continuation of the Old Testament Sabbath, or something entirely new? Does the fourth commandment— "Remember the Sabbath day, to keep it holy" (Exodus 20:8)—still apply to Christians? And in a culture that treats every day as the same, does the concept of a holy day still matter?

These questions have divided Christians for centuries. Seventh-day Adventists insist on Saturday worship. Strict Sabbatarians prohibit virtually all activity on Sunday. Continental Reformed Christians take a more relaxed view, seeing Sunday as a day of worship and rest but not bound by Mosaic Sabbath regulations. And many modern evangelicals treat Sunday as simply the day the church happens to meet—with no particular theological significance attached to the day itself.

This lesson examines the biblical, theological, and historical foundations of the Christian Lord's Day, arguing for a position that honors the creation pattern of rest, the resurrection of Christ, and the freedom of the gospel.

The Creation Sabbath

The Sabbath principle predates the Mosaic law. God rested on the seventh day of creation—"and he rested on the seventh day from all his work that he had done. So God blessed the seventh day and made it holy" (Genesis 2:2–3). This creation rhythm of six days of work followed by one day of rest is woven into the fabric of the created order. It is not merely a Jewish institution; it is a creational pattern—a gift of God to humanity before the fall, before Israel, before the law.

The fourth commandment grounds the Sabbath in this creation pattern: "For in six days the LORD made heaven and earth, the sea, and all that is in them, and rested on the seventh day. Therefore the LORD blessed the Sabbath day and made it holy" (Exodus 20:11). The commandment does not create the Sabbath; it codifies what was already embedded in the structure of creation.

This distinction matters because it affects whether the Sabbath principle survives the passing of the Mosaic covenant. If the Sabbath were purely a Mosaic institution—like the dietary laws or the sacrificial system—it would have been fulfilled and set aside in Christ. But if the Sabbath is a creation ordinance, like marriage and work, it remains binding in principle even though its specific form may change under the new covenant.

From Sabbath to Lord's Day

The New Testament records a striking shift: the earliest Christians began gathering for worship on the first day of the week—Sunday— rather than on the seventh day. The evidence is consistent:

Jesus rose from the dead "on the first day of the week" (Matthew 28:1; Mark 16:2; Luke 24:1; John 20:1). He appeared to His disciples on that first Sunday evening (John 20:19) and again "eight days later"—the following Sunday (John 20:26). The Holy Spirit was poured out at Pentecost, which fell on a Sunday. The church at Troas gathered "on the first day of the week to break bread" (Acts 20:7). Paul instructed the Corinthians to set aside their offerings "on the first day of every week" (1 Corinthians 16:2). John received his Revelation "on the Lord's day" (Revelation 1:10)—almost certainly Sunday.

The early church fathers confirm this pattern. The Didache (c. AD 70–100) instructs Christians to gather "on the Lord's Day" to break bread. Ignatius of Antioch (c. AD 110) speaks of Christians "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." Justin Martyr (c. AD 155) describes the Christian assembly "on the day called Sunday" because it is "the first day on which God, having made a change in darkness and matter, made the world; and Jesus Christ our Savior on the same day rose from the dead."

Reformed Views of the Lord's Day

The Reformed tradition has not been monolithic on the Lord's Day. Three broad positions exist within the tradition.

The Puritan/Westminster position holds that the fourth commandment is a moral law binding on all people in all ages. The Sabbath has been transferred from the seventh day to the first, but its obligations remain: Christians are to rest from all unnecessary labor, recreation, and worldly pursuits, devoting the entire day to worship, works of mercy, and spiritual exercises. The Westminster Confession states that the Lord's Day is to be kept holy "unto the Lord" by "resting all that day from their own works, words, and thoughts about their worldly employments and recreations" (WCF 21.8).

The Continental Reformed position (associated with Calvin and the Three Forms of Unity) takes a more moderate view. It affirms that the Lord's Day is a day for corporate worship and rest but regards the specific Sabbath regulations of the Old Testament as ceremonial rather than moral—fulfilled in Christ and not directly binding on Christians. The Heidelberg Catechism teaches that the Sabbath commandment requires believers to "diligently attend the church of God" and to "rest from my evil works, let the Lord work in me through his Holy Spirit, and so begin already in this life the eternal Sabbath" (Q. 103). The emphasis is on worship and spiritual rest rather than strict cessation from all activity.

The liberty position holds that Christians are free from Sabbath obligations entirely. Paul writes: "One person esteems one day as better than another, while another esteems all days alike. Each one should be fully convinced in his own mind" (Romans 14:5). Colossians 2:16–17 warns against letting anyone "pass judgment on you... with regard to a Sabbath day. These are a shadow of the things to come, but the substance belongs to Christ." On this view, Christians gather on Sunday by apostolic precedent and practical wisdom, but the day itself carries no binding Sabbath obligation.

The Christian Calendar

Beyond the weekly Lord's Day, many churches observe a Christian calendar (or liturgical year) that marks the major events of redemptive history: Advent (the anticipation of Christ's coming), Christmas (the incarnation), Epiphany (the manifestation of Christ to the nations), Lent (preparation through repentance), Holy Week (the passion of Christ), Easter (the resurrection), Ascension, and Pentecost (the gift of the Spirit).

The Reformed tradition has been divided on the Christian calendar. The Puritans rejected it almost entirely, arguing that Scripture prescribes only the weekly Lord's Day as a holy day and that the calendar was a Roman corruption. Other Reformed churches have embraced parts of the calendar— particularly Christmas, Good Friday, and Easter—as valuable opportunities to focus the church's worship on the great events of the gospel.

The case for the Christian calendar is practical and pedagogical: it ensures that the church's worship follows the contours of the gospel story over the course of each year, rather than being driven entirely by the preacher's series choices. A church that observes Advent is reminded annually of the longing for Christ's coming. A church that observes Lent is called annually to self-examination and repentance. A church that moves from Good Friday to Easter Sunday experiences the emotional and theological arc from crucifixion to resurrection in a way that no single sermon can replicate.

The case against the calendar is principial: if the regulative principle governs worship, then only what God has commanded should be observed—and God has not commanded Advent, Lent, or any other season beyond the weekly Lord's Day. Christians are free to observe these seasons but should not be bound to do so.

Conclusion: A Day of Resurrection Joy

The Lord's Day is the church's weekly celebration of the resurrection—the day that reminds every Christian community that death has been conquered, the new creation has begun, and the King is alive. It is a day for worship, for rest, for fellowship, for spiritual renewal, and for the anticipation of the eternal Sabbath when we will rest forever in the presence of God.

In a culture that has lost any sense of sacred time—where every day is the same, where rest is rare, and where worship competes with recreation—the practice of setting apart the Lord's Day is both countercultural and profoundly human. We were made for rhythm—six days of work and one day of rest, scattered living and gathered worship, the ordinary and the sacred. The Lord's Day is God's gift to a weary world: a day to stop, to gather, to worship, and to remember that our ultimate rest is yet to come.