What is the Church? Why is it important to me? Why am I an important part of it?
Church membership is an essential part of a believer's life whether that believer is five or fifty years old. While a young child may not bear all the adult responsibilities involved in membership, yet a full participation in the church's "body life" is meant to be a part of their life in Christ.
The Church is indespensible to believers: Eph 3:10; 4:16; 5:27. Believer's are to be in subjection to elders who are held accountable for them: Hebrews 13:7, 17. The Church has a mission to the end of the Age: Matt 28:18-20. Its purpose includes the growth of believers into Christ's image: Eph 4.
Pentacost is a picture of the church universal in that God's Spirit was poured out on an assemblage from throughout the known world and they heard the Gospel spoken in their own tongues.
The church is made "visible" when believers are visible. As they profess their faith before the world, manifest holy lives and separate themselves from worldliness, they show themselves to be a distinct people of God. They bear the name of Christ and are called "Christians".
The Bible makes it clear that the Lord has called his people to form visible communities of believers, organized with pastors and elders leading the flock, bound together by covenant to love one another and serve the Lord together.
The church was made visible in the days following Pentacost as the new belivers formed into congregations devoted to the Apostles' teaching, to fellowship, to the breaking of bread (Sacraments - Communion?) and to prayer. Apparently the believers were organized into smaller "house churches", but together made up the church. As the missionaries moved out from Jerusalem, they organized congregations of Christians and trained shepherds to minister to them.
Compare these elements that make up a church's "body life" to the marks of the church stressed by the 16th Century Reformers: The preaching of the Word of God; The faithful administration of the Sacraments; Discipline in the lives of Believers; Love and Service
Before we can become a part of the church, we must first be a part of the invisible church. Profession of Faith in Christ and baptism has throughout the history of the church since Pentacost been the way an individual or a family are brought into the church. (Acts 2:38,39; 47).
But just being a part of the invisible church is not enough, we are called to become part of the visible church. Joining a church is an entering into a covenant with God and his people, submitting ourselves to the care and nurture of others and to serving God and one another and it brings with it responsibilities that can not be casually neglected or abandoned.
Consider just a part of what God expects of those who have entered into Church membership:
As an organism, it is a "body composed of different organs or parts performing special functions that are mutually dependent and essential for life." As an organism the eye can't say to the foot, "I don't need you".
On one hand it is a building, on the other a body. As an organization there is government and structure, as an organism every member is important and makes a significant contribution to the whole.
God has defined its structure: It is ruled by Christ though Pastors and Elders (shepherds) and Deacons. Eph 4:11. (cf Acts 20:26-31; 1 Tim 1-12; Titus 1:5-9. 1 Peter 5:1-4))
Hebrews 13:7 and 17 emphasize that that covenant of membership is not to be taken lightly. When God holds the shepherds of the flock accountable for their sheep, it implies that they must know their sheep individually by name and a member of the flock can't just say."I am quitting you and joining another flock."
The only time we should separate ourselves from a group of believers is when either we are geographically separated from them or if, God forbid, the church should depart from the true faith.
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