Here are some quotes from Luther showing that he believed the Catholic Church was a false Church and his followers comprised the true, ancient Church. These quotes are from this website:
socrates58.blogspot.com/2006/06/did-martin-luther-regard-roman.html
… . . they lead all the souls in the world astray . . . just as they reject all the fathers and theologians from their canons, so we reject them from the Church and the Scriptures . . . Now they want to put us out of the Church and the Scriptures, and they cannot get in themselves! . . .
Indeed, since there is nothing in-between, we must be the church of Christ and they the devil’s church, or vice versa. Therefore it all turns on proving which is the true church . . . One part must be false and untrue . . . The Lord Christ commands us not to embrace the false church.
They allege that we have fallen away from the holy church and set up a new church . . . since they themselves boast that they are the church, it is for them to prove that they are . . . But if they cannot prove it . . . they are not the church and . . . we cannot be heretics since we have fallen away from what is not the true church. Indeed, since there is nothing in-between, we must be the church of Christ and they the devil’s church, or vice versa. Therefore it all turns on proving which is the true church . . . One part must be false and untrue . . . The Lord Christ commands us not to embrace the false church. (pp. 193-194)
We have proved that we are the true, ancient church . . . Now you, too, papists, prove that you are the true church or are like it. You cannot do it. But I will prove that you are the new false church, which is in everything apostate, separated from the true, ancient church, thus becoming Satan’s synagogue. (p. 199)
You do not hold to the original, ancient baptism, for you have invented many other new baptisms, teaching that the original baptism is subsequently lost through sin . . . For where there is no baptism, the sacraments, the keys, and everything else are of no avail. (p. 199)
Who can tell all the abominable innovations you have devised in the sacred and holy sacrament of the body and blood of Christ? . . . You have silenced and obliterated the remembrance of Christ . . . [this] makes you a new apostate heretical church, yes, the arch-whore of the devil and the synagogue of hell. For this thing is so hopelessly and abysmally evil . . . the vilest cesspool that the devil has on earth. (pp. 201-202)
We are certainly the true, ancient church, without any whoredom or innovation. (p. 205)
We too were formerly stuck in the behind of this hellish whore, this new church of the pope . . . we regret having spent so much time and energy in that vile hole. But God be praised and thanked that he rescued us from the scarlet whore. (p. 206)
We acknowledge not only that you have, with us, come from the true church and been washed and made clean in baptism . . . but also that you are in the church and remain in it . . . But you are no longer of the church, or members of the church, for in this holy church of God you are building your own new apostate church, the devil’s brothel, with limitless whoredom, idolatry, and innovation. (pp. 209-210)
