Hubner's response was way off the mark, as evidenced by the following line from his response: "Perhaps we should let these heretical Baptists who believe the New Covenant is a regenerate community speak for themselves."
a) Hendryx's objection to Progressive Covenantalism was an objection to the rejection of the visible/invisible distinction.
b) Hendryx specifically identified those Baptists who confess the London Baptist Confession of 1689 as being distinct from the Progressive Covenantalists:
Before we define what the visible/invisible church distinction is, it is important to note that, in stark contrast with Progressive Covenantalism, Classic Covenant Theology (as expressed in the Westminster Standards) and Classic Reformed Baptist Theology (as expressed in the Baptist Confession of 1689), both affirm the visible/invisible church distinction. Drawing on the Westminster Confession, the Baptist Confession of Faith of 1689 chapter 26 states:(emphasis is Hendryx's) (I would also suggest reading LBCF, Chapter 26, for additional context)
"The catholic or universal church, which (with respect to the internal work of the Spirit and truth of grace) may be called invisible, consists of the whole number of the elect, that have been, are, or shall be gathered into one, under Christ, the head thereof; and is the spouse, the body, the fulness of him that fills all in all. 1.1 Heb. 12:23; Col. 1:18; Eph. 1:10,22,23, 5:23,27,32 . All persons throughout the world, professing the faith of the gospel, and obedience unto God by Christ according unto it, not destroying their own profession by any errors everting the foundation, or unholiness of conversation, are and may be called visible saints; and of such ought all particular congregations to be constituted. ( 1 Corinthians 1:2; Acts 11:26; Romans 1:7; Ephesians 1:20-22 ) "emphasis mine.
c) Hendryx did not identify Progressive Covenantalists (much less LBCFers) as "heretical" or "heretics." Quite to the contrary, in a linked document, Hendryx repeats what he wrote previously:
Gentry and Wellum are extremely intelligent, fair, well-spoken men who love the Lord and committed to the Bible and Jesus Christ. They are dear brothers in the Lord.Hubner goes on to try to drive a wedge between Hendryx and James White, but this wedge is misplaced. Hubner should instead realize that Hendryx is criticizing the Progressive Covenantalists, while maintaining the position held by White with respect to visible/invisible distinction.
Thus, White wrote (as quoted by Jamin):
Classically, credobaptists have seen the elect filling the New Covenant (due to its nature), and hence have recognized that the visible church is a mixed body, not to be seen as fully co-extensive with it. Apostasy, then, is viewed as apostasy from a profession of faith, not from membership in the New Covenant. The visible church contains true covenant members and false: but since the New Covenant is inherently soteriological in nature, and is made in the blood of Christ Himself, its members cannot apostatize anymore than Christ can lose His sheep (Jn. 10:27-30) or fail to do the Father’s will (Jn. 6:38-39). Apostasy then is not from the New Covenant, but from false profession of faith in Christ, which may include membership in the visible church.But KtC wrote (pp. 691-692):
As Carson rightly notes, if this biblical and theological understanding of the church is basically right, "then the ancient contrast between the church visible and the church invisible, a contrast that has nurtured not a little ecclesiology, is either fundamentally mistaken, or at best of marginal importance." Why? Because the New Testament views the church as a heavenly community (i.e., tied to the age to come and the new creation, not "in Adam" but "in Christ") and a spiritual community (i.e., born of and empowered by the Spirit in faith union with Christ), living her life out now while she awaits the consumation, literally "the outcropping of the heavenly assembly gathered in the Jerusalem that is above."(emphasis in original)
And the New Testament is clear: to be "in Christ" and thus in the new covenant, a member of his gathered people (church), means that one is a regenerate believer. The New Testament knows nothing of one who is "in Christ" who is not regenerate, effectually called of the Father, born of the Spirit, justified, holy, and awaiting glorification.
How does covenant theology respond to this analysis, since they continue to affirm the "mixed" nature of both Israel and the church? Probably the most significant response is an appeal to the warning/apostasy passages of Scripture in order to demonstrate that the visible church is a "mixed" community, just like Israel of old (see, e.g., Heb. 6:4-6; 10:26-39). Do not these text demonstrate that it is possible for some people to be members of the new covenant community but then, sadly, to depart from the faith, thus demonstrating that they were never regenerate, believing people even though they were externally members of the church? We can give only a brief reply to this assertion as we note three problems with this response.
Thus, while Dr. White affirms the mixed nature of the church and the visible/invisible distinction, KtC does not.
Of course, that does not mean that White and Hendryx agree on everything. I think an important difference between Hendryx and White would be that Hendryx would view the visible church as the New Covenant Community, in this life, and that White views the invisible church as the New Covenant Community in this life. Naturally, a lot more nuance would be helpful, but what is unhelpful is suggesting that Hendryx thinks that either Progressive Covenantalists or LBCFers are "heretical," when Hendryx specifically distinguishes between them.