As we noted in our study on the church’s Apostolicity, the mere claim to be Apostolic is insufficient to prove that a church is, indeed, Apostolic. A church is Apostolic only if it follows the Apostolic gospel. We face a similar reality when a corporate body claims to be a church. A gathering of people can make the claim to be a church, but how do we know if said gathering is a true church? Historically, Protestants and Roman Catholics have answered this question very differently. For the Church of Rome, a true church exists when it has a bishop who can trace his line of succession back to the Apostles. In the final analysis, this means that a true church must be in communion with the bishop of Rome—the pope. In the traditional Roman Catholic view, only Roman Catholic parishes in submission to the pope constitute the true church of Jesus Christ. Whatever else may be said about the aformentioned view, the marks of a true church must be tested finally against the teaching of Scripture, which is the sure instruction of the Apostles and the inerrant Word of God. Protestants have traditionally agreed on two marks: the right preaching of the Word and the right administration of the sacraments. Many list church discipline as a third mark of the church. Others make it part of the right administration of the sacraments, as discipline determines who may receive these means of grace. The right preaching of God’s Word is an obvious mark of the church. Without faithfulness to the foundation of Christian belief, no group can rightly call itself Christian, let alone a church. Summaries of the essential teaching of Scripture such as the Nicene Creed and Westminster Confession of Faith can assist us in determining whether a particular church accurately preaches the Word. Sacraments are visible words of God, so their right administration also marks a true church. Today’s passage proves that the earliest Christians affirmed these two marks of the church, for the first New Testament church devoted itself to Apostolic teaching and the breaking of bread (the Lord’s Supper) (Acts 2:42). Word and sacrament, rightly administered, were the emphasis of the Apostolic church, and so they must be our emphasis today.