“Therefore since this argument is waxing warm in our day, you must be prepared to give this account and reply: the term “Christian Church” has a double meaning, as other words do too. For there is a true and there is a false church. Now show me the true church. The pope claims to be the true church, but how is he going to prove it? He has the Gospel and Baptism; so do we. The issue is: Who has the true Gospel and Baptism, and who the false? The one Christ is the true one, but all heretics fashion a new Christ. Words have double meanings. Every heretic assigns a special meaning to a word, and he also employs the terms used in the divine Word. The term “god,” for example, is given the most manifold meanings. I suppose there are a thousand different gods.
Mammon is a god. So are the Order of St. Francis and the Carthusian Order. Everybody has his own peculiar god. Therefore you must be wary. Just as the word ‘god’ really pertains only to the one God but is perverted and applied so variously, thus “Christian Church” is also misused and loosely used. You must pay no attention to them when they say: “Here is the church.” Your answer must be: ‘I am well aware that there is one Christian Church, and I know the term ‘Christian Church’ very well. But it is news to me that you are that church. You may indeed vaunt that you are the Christian Church, but that beautiful name by itself will not mislead me. I know that the heretics are to deck themselves with the fine name of God, of Christ, and of the Christian Church, and thus deceive the world’” (Luther’s Works, v. 23, p. 288).