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Q. What are the main differences between the Missouri Synod and the Wisconsin Evangelical Lutheran Synod (WELS)?
A. From the LCMS perspective, the three main theological differences between the LCMS and the WELS are the following:
1) The biblical understanding of fellowship.
The WELS holds to what is called the "unit concept" of fellowship, which places virtually all joint expressions of the Christian faith on the same level. In an official statement made in 1960 the WELS states, "Church fellowship should therefore be treated as a unit concept, covering every joint expression, manifestation, and demonstration of a common faith" (Doctrinal Statements of the Wisconsin Evangelical Lutheran Synod, 1970, pp. 51-52). The LCMS, however, has historically not understood or practiced church fellowship in this way. Our Synod, for example, has made a distinction between altar and pulpit fellowship (for which full doctrinal agreement is required) and other manifestations of Christian fellowship, such as prayer fellowship (which do not necessarily require full doctrinal agreement). Disagreements on this issue led the Wisconsin to break fellowship with the LCMS in 1961.
2) The doctrine of the ministry.
With respect to the doctrine of the ministry, since the days of C. F. W. Walther our Synod has held that the office of the public ministry (the pastoral office) according to the Scriptures is the one divinely established office in the church, while the church possesses the freedom to create other offices, by human institution, from time to time to assist in the carrying out of the functions of the pastoral ministry. The WELS' Theses on Church and Ministry, however, expressly deny that the pastoral ministry is specifically instituted by the Lord in contrast to other forms of public ministry (see Doctrinal Statements, pp. 9-11; cf. the Commission on Theology and Church Relations' 1981 report on The Ministry: Office, Procedures, and Nomenclature.
3) The role of women in the church. While both the LCMS and the WELS strongly oppose the ordination of women to the pastoral office on Scriptural grounds, the LCMS has concluded that the Scriptures do not forbid woman suffrage in the church. The WELS opposes woman suffrage in the church as contrary to the Scriptures.