When we think of the human body and how intricately woven all its members are, we begin to understand why the Lord uses this analogy of his church. We the church, like the human body, are a living organism in which each member is intricately woven together functioning by the power of the Holy Spirit to the praise and glory of God. Such a concept makes it clear how important church membership is and how important it is to be an active member as well. Many people do not like the idea of joining a church because they see it as oppressive and unnecessary. However the bible makes it clear that coming to faith automatically makes us members of the universal church, thus becoming a member of a local church is simply the visible expression of our membership to the larger body of Christ. It demonstrates that we understand that the local church is where God wants us to grow and develop with other members and be discipled. It is where we practically serve the interests of others fulfilling the Great Commandment of loving one another, and where we recognize that just as Christ has authority over the church universal, he has appointed elders in each church representing his spiritual authority as stewards of his word.
Clearly the bible teaches in Hebrews 13:17
"Obey your leaders and submit to them, for they are keeping watch over your souls, as those who will have to give an account. Let them do this with joy and not with groaning, for that would be of no advantage to you." This is not a suggestion but a command. The Lord knows that we are prone to wander away from him and in his grace provides under-shepherd to care for and direct his sheep. When true biblical eldership is in place in any local assembly the members of the church will reap the spiritual benefits. However sadly in our day, there is a lack of qualified men serving as elders, and a lack of appreciation from members for those who do.
The point I really wanted to make, was that because the local church is the body of Christ joining a healthy church is access to the life of Christ. Not joining a local church is NOT having access to the life of Christ. This is why church discipline is so important. It recognizes the covenant blessings of those who are members of the church and when one is removed from the church they are considered,
"handed over to Satan" 1 Cor. 5:5 and
"counted as a heathen" Matt. 18:17. Being dis-membered from the body of Christ is equivalent from being cut off from the covenant community. Just like cutting a limb off of your body cuts it off from the life that flows through your blood. When thinking of it this way, joining a church should be the desire of every true born again believer. Why? To partake of the life of Christ and to participate in the covenant blessing.
I believe the parable of the vine illustrates the principle I have just wrote about. Read the following:
John 15:1-6 “I am the true vine, and my Father is the vinedresser. Every branch in me that does not bear fruit he takes away, and every branch that does bear fruit he prunes, that it may bear more fruit.Already you are clean because of the word that I have spoken to you. Abide in me, and I in you. As the branch cannot bear fruit by itself, unless it abides in the vine, neither can you, unless you abide in me. I am the vine; you are the branches. Whoever abides in me and I in him, he it is that bears much fruit, for apart from me you can do nothing. If anyone does not abide in me he is thrown away like a branch and withers; and the branches are gathered, thrown into the fire, and burned.
Just as a branch cannot continue to live and produce grapes unless it is joined to the vine from which the life giving sap flows…A Christian cannot bear spiritual fruit in progressive sanctification unless one has spiritual union with Christ, from which all the life giving grace flows through the Holy Spirit.Our union to Christ will be made evident when we join the only institution on earth where his presence dwell in power and authority. The church is simply the best place on earth where we grow in our relationship with God and grow in our relationships to others. To come to church and take all the benefits without becoming a members is no different than having premartial sex, and enjoying all the benefits of marriage without making a commitment.