Where the traditions land
Answer | Seated traditions | By population |
Yes — through convergence toward the one true Church | Catholic, Eastern Orthodox, Oriental Orthodox, LDS | ~80% |
Yes — through active dialogue toward visible reunion | Anglican, Lutheran | ~8% |
Unity already exists spiritually; visible unity is secondary | Reformed/Presbyterian, Methodist/Wesleyan | ~6% |
No — not pursued; doctrinal agreement must come first | Southern Baptist Convention, Pentecostal (Trinitarian), Seventh-day Adventist | ~6% |
No — other Christian bodies are to be left, not united with | Jehovah's Witnesses | under 1% |
Population figures are each tradition's own most recent published count. Eligibility is set against the World Christian Database, the standard reference for global denominational data.
Why the disagreement
Every seated tradition affirms some form of Christian unity is real or possible, but "unity" doesn't mean the same thing across this table, which is most of the disagreement right there. Catholic, Orthodox, and LDS teaching share the same underlying structure despite their real differences: each holds that the one true Church already exists as a specific, identifiable body — Rome, the Orthodox communion, or the restored Church — and that unity means other Christians converging toward it, not a merger of equals. Catholic teaching softened this considerably after Vatican II, recognizing "elements of sanctification and truth" outside its own visible structure; Orthodox teaching remains internally divided over how far that openness should go, with some bishops treating dialogue as hopeful and others calling it a "pan-heresy."
Anglican and Lutheran teaching pursue something different: formal dialogue toward visible reunion between traditions that don't claim sole possession of the true Church. Anglican teaching has a specific, century-old proposal for what that requires — the Chicago-Lambeth Quadrilateral — and Lutheran-Catholic dialogue produced a genuine doctrinal agreement in 1999 on the exact issue that started the Reformation split.
Reformed and Methodist teaching locate real unity somewhere else: already achieved, invisibly, among genuine believers regardless of denomination, which makes visible merger secondary rather than urgent — Wesley's founding instinct was that Christians who "cannot think alike" could still "love alike" without one visible structure at all.
Southern Baptist, Pentecostal, and Adventist teaching approach visible unity with doctrinally different bodies cautiously, prioritizing agreement first; Jehovah's Witnesses go further, treating other Christian bodies collectively as corrupted and something to leave rather than unite with.
Solving the disagreement
The traditions claiming to already be the one true Church — Catholic, Orthodox, LDS — would need the same premise settled that keeps recurring in this format: which body actually holds the authority it claims to hold, a question none of their own texts can adjudicate from outside itself, since each tradition's claim to that authority is exactly what's in dispute.
Anglican and Lutheran teaching offer the one genuine counter-example in this whole project to "nothing ever resolves." The 1999 Joint Declaration on the Doctrine of Justification is real, substantive doctrinal convergence between Lutheran and Catholic teaching on the specific issue that caused the original 16th-century split — proof that incremental theological agreement is possible, even if it hasn't produced full institutional reunion.
Reformed and Methodist teaching aren't waiting on anything, by their own account: if real unity already exists invisibly among believers, there's no gap left needing external resolution, only a separate, secondary question about whether visible structures should also merge.
For Southern Baptist, Pentecostal, Adventist, and Jehovah's Witness teaching, what's missing isn't a resolvable dispute so much as a bar that hasn't been cleared: each would require the other side's doctrine to change enough to satisfy positions they already hold, which isn't a fact anyone could discover so much as a persuasion that hasn't happened yet.
Sources
Same standing source per tradition on every post, not hunted per question.
- Catholic — Catechism of the Catholic Church
- Eastern Orthodox — Nicene-Constantinopolitan Creed (binding across all jurisdictions); The Longer Catechism of St. Philaret of Moscow (widely used, not binding on every jurisdiction)
- Oriental Orthodox — Catechism of the Coptic Orthodox Church, Fr. Tadros Y. Malaty (Amazon — no full free text found)
- Anglican — Thirty-Nine Articles of Religion
- Lutheran — Book of Concord
- Reformed/Presbyterian — Westminster Confession of Faith
- Methodist/Wesleyan — Articles of Religion
- Southern Baptist Convention — Baptist Faith & Message 2000
- Pentecostal (Trinitarian) — Assemblies of God Statement of Fundamental Truths
- Seventh-day Adventist — 28 Fundamental Beliefs
- LDS — Book of Mormon and Doctrine and Covenants
- Jehovah's Witnesses — What Does the Bible Really Teach?