The Church is the Body of Christ (1 Corinthians 12:12-13), composed of all who are born again during this age of grace (Ephesians 3:6). The Great Commission was given to the Church and this task of world evangelism and discipleship is the responsibility of the Church today (Matthew 28:19-20).
In Matthew 16:18, Christ mentions “church” for the first time. However, many of the laws which are found in the Old Testament, directed specifically to the nation of Israel, are given directly to the New Testament church in the New Testament. In this sense are they to be interpreted and obeyed. The Church, although mentioned in Matthew 16:18, did not have its formal beginning until Acts 2, at Pentecost. All true believers, since Pentecost, who have been placed (baptized) into the body of Christ, by the Spirit, are members of the Church.
The local bodies of believers are to be organized under only one head, the Lord Jesus Christ (Ephesians 1:22).
The Lord, prior to His ascension, instituted two ordinances which are to be perpetuated by the local church. These ordinances include baptism and communion.
The significance of the baptism ordinance is that the believer might be identified with both the Lord and the local church. The mode of baptism to be practiced is total immersion (only after the individual has made a profession of faith and fully understands the significance of the ordinance) (Matthew 3:16; Acts 8:39; Romans 6:4). Water baptism is not mandatory in order to be identified with a particular local assembly, but is a matter of obedience, between the Lord and the individual, not to be taken lightly.
The communion ordinance is one which is to be taken very seriously in the light of the serious admonitions found in 1 Corinthians 11. This ordinance should never be required, lest someone should partake “in an unworthy manner.” Each believer (and only believers) should carefully examine himself prior to partaking of the elements (1 Corinthians 11:27-32). Jesus instituted communion as a memorial for His death, a time when believers can remember His body that was delivered up on their behalf (Luke 22:14-20).