The UPCI worships on Sunday as the day of Christ's resurrection and the New Testament pattern for Christian assembly. The Mosaic Sabbath commandment is understood as part of the old covenant law that is not binding on New Testament believers in its specific regulations. Christians observe the Lord's Day — Sunday — as the appropriate time for communal worship, not Saturday as mandated by the Mosaic law.

The UPCI is known for its intensive worship culture, which typically includes not only Sunday morning services but Sunday evening and midweek (often Wednesday and Friday) services as well. Prayer meetings, revival services, and camp meetings are regular features of UPCI community life. This frequent gathering reflects the denomination's emphasis on corporate Spirit-filled worship rather than a specific Sabbatarian theology.

The UPCI does not impose specific restrictions on Sunday activities beyond participation in church services. The holiness standards the UPCI does maintain — regarding dress, entertainment, and lifestyle — are framed as expressions of separation from worldliness rather than as Sabbath regulations.