Institues of Elenctic Theology by Francis Turretin

The church of Rome can be regarded under a twofold view: either as it is Christian, with regard to the profession of Christianity and of gospel truth which it retains,; or papal, with regard to subjection to the pope, and corruptions and capital errors (in faith as well as in morals) which she has mingled with and built upon those truths besides and contrary to the word of God. We can speak of it in different ways. In the former respect, we do not deny that there is some truth in it; but in the latter (under which it is regarded here) we deny that it can be called Christian and apostolic, but Antichristian and apostate. In this sense, we confess that it can still improperly and relatively be called a Christian church in a threefold respect. First, with respect to the people of God or the elect still remaining in it, who are ordered to come out of her, even at the time of the destruction of Babylon (Rev. 18:4). (2) With respect to external form or certain ruins of a scattered church, in which its traces are seen to this day, both with respect to the word of God and the preaching of it (which, although corrupted, still remains in her); and with respect to the administration of the sacraments and especially of baptism, which is still preserved entire in her substance. (3) With respect to Christian and evangelical truths concerning the one and triune God, Chirst the God-man Mediator, his incarnation, death and resurrection and other heads of doctrine by which she is distinguished from assemblies of pagans and infidels. But we deny that she can simply and properly be called a true church, much less one and only catholic church, as they contend.

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