Quoting from Thesis III of C.F.W. Walther's presentation to the 15th Western District Convention in 1870:
Matt. 10:32-33: “Therefore, he who confesses Me publicly, him will I confess before My Father in heaven. But one who denies Me publicly, him will I also deny before My Father in heaven.” This too is a main passage to prove that one should stick to the right, i.e., the true visible church; not because—as the papists wrongly say—one is a Christian and saved only in the church, but because one is obligated to profess. And this is necessary not for God’s sake, but for the sake of ourselves and of the fellow-redeemed world. For it is God’s will that all people should be saved through the Gospel. But the Christians should preach it to and profess it before the world, not as though they all should or must be public servants of the church, but in such a way and in order that they will stick to the true visible church, hear the pure Gospel in it, and with it profess the same and defend [it] against opposition. In this way the church is a saving leaven in the world.
C.F.W. Walther, Essays for the Church, Vol. 1 (St. Louis: Concordia, 1992) 209.
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