When Pius IX was concerned about Modernism in the 19th century, so was a notable Lutheran minister in the United States.

The Revd Charles Porterfield Krauth was a learned man.  Indeed, his father, also a Lutheran clergyman, was a university president.  Krauth was concerned about the dilution of American Lutheranism and wrote the Akron-Galesburg Rule which stated that only Lutheran pastors could preach from Lutheran pulpits and that only Lutherans could receive the Lord’s Supper at Lutheran altars.  Krauth and his conservative followers eventually formed the General Council of the Evangelical Lutheran Church in America in 1867. (Not to be confused with the present-day ELCA!) Most of the original state synods involved have over the years evolved and separated, the best known being the LCMS (Missouri) and WELS (Wisconsin).

in 1872 Krauth wrote his most famous work, The Conservative Reformation and Its Theology.  What the late Fr John Neuhaus — a convert to Catholicism from the LCMS — called Neuhaus’s Law was actually taken from Krauth’s description of ecclesiastical error. 

What Krauth wrote is just as true now as it was then. Note how he describes error coming in quite innocently and asking for tolerance (emphasis mine):

But the practical result of this principle [of the church tolerating within her bosom those who claim she is teaching error] is one on which there is no need of speculating; it works in one unvarying way. When error is admitted into the Church, it will be found that the stages of its progress are always three. It begins by asking toleration. Its friends say to the majority: You need not be afraid of us; we are few, and weak; only let us alone; we shall not disturb the faith of others. The church has her standards of doctrine; of course we shall never interfere with them; we ask only for ourselves to be spared interference with our private opinions. Indulged in this for a time, error goes on to assert equal rights. Truth and error are two balancing forces. The Church shall do nothing which looks like deciding between them; that would be partiality. It is bigotry to assert any superior right for the truth. We are to agree to differ, and any favoring of the truth, because it is truth, is partisanship. What the friends of truth and error hold in common is fundamental. Anything on which they differ is ipso facto non-essential. Anybody who makes account of such a thing is a disturber of the peace of the church. Truth and error are two co-ordinate powers and the great secret of church-statesmanship is to preserve the balance between them. From this point error soon goes on to its natural end, which is to assert supremacy. Truth started with tolerating, it comes to be merely tolerated, and that only for a time. Error claims a preference for its judgments on all disputed points. It puts men into positions, not as at first in spite of their departure from the Church’s faith, but in consequence of it. Their recommendation is that they repudiate that faith, and poistion is given them to teach others to repudiate it, and to make them skilful in combating it. (From The Conservative Reformation and Its Theology. Philadelphia: J.B. Lippincott & Co., 1872, pp. 195-96.)

This strategy was the same for the Lutheran Church that Krauth examined, the Presbyterian Church that Gresham Machen encountered in the 1920s (we haven’t had that story yet), Vatican II in the Catholic Church, institutional changes in the Episcopal Church and the Anglican Communion as well as changes in the theology of evangelical churches and, last year, the resolution approved in the ELCA.  It is rampant.  It is no different to a cancer.

This time-honoured formula is guaranteed to work every time.  So, watch for the wolf in sheep’s clothing disguised as a pitiful, marginal victim.  It was a symptom of modernism and it is a symptom of postmodernism.  Be very careful of what ‘new idea’ you are asked to accept at church, be it rules, liturgy, music, sermons.  If your inner fundamentalist says ‘no’ when you hear them, please listen to that little voice and turn away.  These can potentially — and often do — go against your denomination’s teachings and confessions of faith, both of which are based on Scripture. 

Follow truth, not the crowd.