Saturday Sabbath observance is one of the most distinctive and non-negotiable Adventist beliefs. The Seventh-day Adventist Church teaches that God instituted the seventh-day Sabbath at creation (Genesis 2:1–3), enshrined it in the Decalogue (Exodus 20:8–11), observed it in Jesus' example, and that it was never changed to Sunday by divine authority. Sunday observance is traced to human ecclesiastical tradition, not Scripture.

The Adventist Sabbath is observed from sundown Friday to sundown Saturday (following the biblical pattern of evening-to-evening). It involves abstaining from secular work and commerce, worship, fellowship, and rest. Adventism sees the Sabbath as a sign of God's creative and redemptive authority (Ezekiel 20:12) and expects its renewed universal importance in the final period of earth's history. This conviction is embedded in the church's identity and is one of its three distinctive prophetic emphases (along with the sanctuary and the state of the dead).