Watching sports on Sunday is not sin. The New Testament is explicit that Christians are not bound by Sabbath regulations (Colossians 2:16-17, Romans 14:5-6). The Lord's Day (Sunday) is celebrated as the day of resurrection, not as a transfer of Mosaic Sabbath law. The practical questions are about wisdom and prioritization: Is Sunday worship being consistently deprioritized for sports? Is the content of what's being watched appropriate? 72/100 Spiritually Safe — not a sin issue, but a stewardship and priority issue worth thinking about.
The question of watching sports on Sunday is really a question about Sabbath theology — does the Old Testament's Saturday Sabbath command apply to Christians, and if so, does it transfer to Sunday?
The New Testament is remarkably explicit on this. Colossians 2:16-17 — "Therefore do not let anyone judge you by what you eat or drink, or with regard to a religious festival, a New Moon celebration or a Sabbath day. These are a shadow of the things that were to come; the reality, however, is found in Christ." Romans 14:5-6 — "One person considers one day more sacred than another; another considers every day alike. Each of them should be fully convinced in their own mind. Whoever regards one day as special does so to the Lord." These texts establish that Sabbath observance is not binding on New Testament Christians.
Christians gather on Sunday (the first day of the week) because Jesus rose on the first day (Luke 24:1, John 20:1). The early church gathered on the first day to break bread (Acts 20:7) and take collections (1 Corinthians 16:2). Sunday is "the Lord's Day" (Revelation 1:10) — a celebration of the resurrection, not a transfer of the Mosaic Saturday Sabbath.
The Puritan tradition developed a "Christian Sabbatarianism" that treated Sunday with strict Sabbath regulations — this tradition is found in some Reformed and Presbyterian churches and is a legitimate application of conscience-based conviction (Romans 14:5). But it is not binding on all Christians.
While watching sports on Sunday is not sin, several wisdom questions are worth asking: Is Sunday corporate worship consistently deprioritized when sports is on? (Hebrews 10:25 — "not giving up meeting together") Are the specific games or content being watched consistent with Philippians 4:8? Is the time spent with family, rest, and renewal — or is it compulsive consumption? These are stewardship questions, not sin questions. See our Is It a Sin? hub and our guide on Is It a Sin to Be Lazy? The GotQuestions treatment of Sunday and the Sabbath provides thorough theological background.