“First, the holy Christian people are recognized by their possession of the holy word of God.” Martin Luther always returned to the foundational importance of the Scriptures and the gospel in his approach to any doctrinal question. The church must have and cherish the revelation of God. “And even if there were no other sign than this alone, it would still suffice to prove that a Christian, holy people must exist there, for God’s word cannot be without God’s people, and conversely, God’s people cannot be without God’s word.”
“Second, God’s people or the Christian holy people are recognized by the holy sacrament of baptism, wherever it is taught, believed, and administered correctly according to Christ’s ordinance.” The church possessed and administered the sacrament of baptism as taught in the Bible, a visible expression of the gospel.
The Lord’s Supper
“Third, God’s people, or Christian holy people, are recognized by the holy sacrament of the altar, wherever it is rightly administered, believed, and received, according to Christ’s institution. This too is a public sign and a precious, holy possession left behind by Christ by which his people are sanctified so that they also exercise themselves in faith and openly confess that they are Christian, just as they do with the word and baptism.” Again, the sacrament of the Lord’s Supper must be treasured by the church as Christ has taught it in the Bible.