This question strikes me as fundamental to understanding why some denominations and sects hold their organization's publications and affirmations in such high regard. My answer to the question is in a word, never. Can I trust an ecclesiastical document to guide me in matters of faith? There is certainly great value in the wisdom of men led by God to provide guidance to the church (1 Ti 3:15). However, the Protestant Reformation is guided by a fundamental acceptance that it is scripture alone that determines what we believe in. How can we hold to Sola Scriptura as many are quick to claim and at the same time pledge some sort of allegiance to Sectarian creeds. I recall a conversation with a high church Calvinist recently in which he made an interesting statement. As part of his becoming a member of that church he decided to participate in taking an oath of acceptance to God regarding the Westminster Confession of Faith. Aside from the disobedience to Christ for making such an oath (Mt 5:34-36), how is it that a mere man can swear to God to live by the fallible opinions of men gathered in the 17th century? Having lived a life sworn to an ecclesiastical document and rejected as ecumenical, how does such a soul answer the LORD if and when shown to be in error? Each of our churches have statements of faith identifying the ground upon which we stand. Most of us as Protestant embrace Sola Scriptura as the defining guide to what we are to believe yet none should in turn let our faith be grounded in what other fallible men determined in another age or in this age.
The Confessional period of the Protestant Reformation during the 17th century was a response to the state of competing ideologies among Calvinistic churches following the passing of the great early reformers. The English, Swiss, German and Low Country churches defined themselves with varying yet similar documents committing their beliefs to paper giving their adherents a sense of community. The Confessions are in a real sense the first denominating of the Protestant church into competing sects. Presbyterians compete with Baptists who in turn compete with Congregationalists and as Protestantism continued in growth, the denominations continued. The Confessions alone are not bad or ill-advised. We each as Christians hold to a Confession, one I regard as a true confession and necessary, infallible in every respect (Ro 10:8-11). That scriptural truth can be subscribed to by all Christians and represent the ground of our faith. Yet, can the Arminian turn around and include an affirmation of the various doctrines of Prevenient grace as a ground of his faith being a Christian? I would hope not even though I affirm that doctrine as best representing how God enables men to turn toward Him. By not doing so, we confirm scripture as the only infallible ground upon which we stand.
Sometimes looking at statements of faith is a good indication of what people believe. Just as often though such statements are merely generic, empty platitudes that do not reflect what is taught and held to. Occasionally we encounter statements that need further examination, not because those who subscribe to it are bad guys or heretics, but because it draws attention to things extra-biblical. Can we ground our faith by what we embrace as a statement of our faith in Christ? I was going to present a statement in particular but not wishing to offend any brethren I will condense my observation to this. Part of the statement of faith included a section declaring the creeds and confessions of the Calvinist Church determined in the 17th century as being led by the Holy Spirit and representing the wisdom and pillar of the church. Now, if a confession of faith is such that I as a Christian cannot in any way endorse it, is it really a Christian Confession. I cannot limit this objection to Calvinists. Arminians, Baptists and others do the same. I have done so. Everybody I can think of has done so but the question lingers. Is this proper in defining our faith? Now, I may reconsider and revise these thoughts as I dwell on them. I may even strike them completely if convinced otherwise. For now, I am inclined to avoid lifting any Confession other than that of scripture to a place of preeminence as I define my faith.