I am not endorsing or promoting Francis Turretin as a true Christian when I quote from him (nor anyone cited by Turretin). But I think he puts forth interesting information (any underlining emphasis is mine).
“The author of the commentary on the Psalms under the name of Jerome on Psalm 133: ‘The church does not consist in walls, but in the truth of doctrines. The church is there, where true faith is. But fifteen or twenty years before, all these walls of the churches here held heretics. The church, however, was there, where true faith was’ (Breviarium in Psalmos [PL 26.1296] on Ps. 133). Ambrose: ‘The faith therefore of a church especially is commanded to be sought, in which if Christ is a dweller, it is undoubtedly to be chosen, but if the people are faithless or a heretical teacher deforms the dwelling, the communion of heretics is to be avoided, it is to be considered a synagogue to be shunned’ (Expositions in LMcam 6.68 [PL 15.1772] on Lk. 9:5).
Augustine: ‘Let us not hear, I say this, you say that; but let us hear, the Lord says this…There let us seek the church; there let us decide our cause’ (Contra Donatistas: De Unitate Ecclesiae 3.5 [PL 43.394]). ‘I have the most manifest voice of my pastor commending to me, and without any hesitation setting forth the church, I will impute it to myself, if I shall wish to be seduced by the words of men and to wander from his flock, which is the church itself, since he specially admonished me saying, my sheep hear my voice and follow me; listen to his voice clear and open and heard; who does not follow him, how will he dare to call himself his sheep?‘ (ibid., II.28 [PL 43.410]).
‘To salvation itself and eternal life no one comes, except him who has the Head, Christ. No one, however, could have the Head, Christ, except him who was in his body, which is the church, which we ought to recognize as the head itself in the sacred canonical Scriptures; not to seek it in the various rumors and opinions of men, and in their deeds and words. Let them demonstrate their church if they can, not in the discourses and rumors of Africans, not in the councils of their bishops, not in the writings of any disputants, not in deceitful signs and wonders. But in the prescription of the law, in the predictions of the prophets, in the singing of Psalms, in the words of the shepherd himself, in the preaching of the evangelists, i.e., in all the canonical authorities of the sacred books’ (ibid, 18 .47 [PL 43.427-28]).
‘The question between us and the Donatists is, where is the church? What, therefore, are we to do? Are we to seek it in our words or in the words of its Head, our Lord Jesus Christ? I think we ought the rather to seek it in the words of him who is the truth and best knows his own body’ (ibid., 2.2 [PL 43.392]). Many such things proving our point are to be found in the same place which we omit for the sake of brevity. ‘In the Scriptures we have learned Christ, in the Scriptures we have learned the church, we have these Scriptures in common, why shall we not retain both Christ and the church in them?” (Letter 105, ‘To the Donatists’ [FC 18:206; PL 33.401]). Vincent of Lerins, as Sixtus Senensis observes, lays down the authority of the Scriptures as the first rule of discerning a true church from a heretical church (Bibliotheca sancta 6, annot. 104 [1575 ], 2:153)” (Turretin).
A wicked lust for walls, numbers, and ignorant zeal (cf. Romans 10:1-4) will NEVER seize upon true Christians; nor will any fear of a common two-pronged false charge of “novel” and “cultic.” To those who ask us:
“Where was your church before such-and-such a date?” or “How many people throughout church history do you suppose have held views that correspond to yours?”
“To the Law and to the Testimony!” (Isaiah 8:20)
So let’s have a test-case Bible study regarding the “cultic” and “novelty” charges, and let’s see who is saying nothing else than what God through the prophets and Moses said.
“But I confess this to you that according to the Way, which they say [is] a sect, so I worship the ancestral God believing all things according to that having been written in the Law and the Prophets, having hope toward God, which these themselves also admit, [of] a resurrection being about to be of [the] dead, both of just and unjust ones. And in this I exercise myself to have always a blameless conscience toward God and men” (Acts 24:14-16).
“Because of these things, having seized [me] in the temple, the Jews tried to kill [me]. Then obtaining help from God, I stand until this day, witnessing both to small and to great, saying nothing else than what the prophets and Moses also said was going to happen: whether Christ [was] liable to suffer, whether first by a resurrection of [the] dead He was going to proclaim light to the people and to the nations. And he defending himself [with] these things, Festus said with a loud voice, Paul, You rave! Your many letters turned [you] into madness. But he said, Not to madness, most excellent Festus, but I speak words of truth and sanity. For the king understands about these things, to whom I speak, even being bold of speech. For I am persuaded not any of these things are hidden [from] him, nothing. For [the] doing of this is not in a corner. Do you believe the prophets, king Agrippa?” (Acts 26:21-27)