Martin Luther, The Large Catechism, The Apostles' Creed, Article III, paragraphs 43-45:
43] For where He does not cause it to be preached and made alive in the heart, so that it is understood, it is lost, as was the case under the Papacy, where faith was entirely put under the bench, and no one recognized Christ as his Lord or the Holy Ghost as his Sanctifier, that is, no one believed that Christ is our Lord in the sense that He has acquired this treasure for us, without our works and merit, and made us acceptable to the Father. What, then, was lacking? 44] This, that the Holy Ghost was not there to reveal it and cause it to be preached; but men and evil spirits were there, who taught us to obtain grace and be saved by our works. 45] Therefore it is not a Christian Church either; for where Christ is not preached, there is no Holy Ghost who creates, calls, and gathers the Christian Church, without which no one can come to Christ the Lord. 46] Let this suffice concerning the sum of this article. But because the parts which are here enumerated are not quite clear to the simple, we shall run over them also.
It seems that Dr. Martin Luther is denying here the fact of the Church's existence among the Roman Catholic Church of his time. I've learned here that while claiming that there were a lot of non-Christians in the Roman Catholic Church of his time, he still didn't consider all the clerics of the Roman Catholic Church as surely not the Church, however, these words that I just read in his Large Catechism (see the quotation above) seem to say the opposite. Can anyone, please, clarify this?