Why must a man and a woman make a vow to one another in a public wedding ceremony in order to be married? Why can't a couple pledge their love for each other in private? Are we indentured to a cultural tradition or is there a biblical principle at work?
Ultimately, what underlies the wedding ceremony is a promise or an oath that the betrothed make to one another. They both promise to love one another until death separates them. This oath is taken in the presence of God and the church to hold the couple accountable to their promises. But what does a marriage ceremony have to do with church membership?
Well, the principles of the marriage ceremony are very similar to those involved with church membership. Just as a couple profess their love before God and the church so too a person stands before God and the church to profess faith in Christ and commitment to His Body. This public profession of faith is done with Matthew 10.32 in mind: "Whoever confesses Me before men, him I will also confess before My Father..." Now, this is not all there is to church membership just as a wedding vow is not all there is to a marriage.
As previously stated, in a wedding ceremony both God and, ideally, the church hold the couple accountable to their vows. Likewise, when a person makes a public profession of faith in Christ that person does so in the presence of God and the local body. God has ordained that the church and its elders hold the person accountable to live a life that matches his profession of faith. We see this principle spelled out in Hebrews 10.24-25: "Let us consider one another in order to stir up love and good works, not forsaking the assembling of ourselves together, as is the manner of some, but exhorting one another, and so much the more as you see the Day approaching."
So, then, with these two principles in mind, making a public profession of faith conjoined with the need for accountability, we see the importance of church membership. When a believer unites with a local church body he is not only telling the world that he trusts in Christ alone for his salvation but he is also willingly submitting to church leadership and asking them to hold him accountable to walk in righteousness. The Christian who never joins a church is much like a man who lives with a woman without ever making a public declaration and commitment of his love for her. In that situation the man or woman is always free to leave because they are under no obligation to stay togetherâ€”no accountability. If this situation is universally rejected by Christians as an unacceptable way to conduct a relationship between a man and a woman, should we expect any less from the relationship between God and His church?
Now, one last element must be taken into consideration. In marriage, some people are able to find mates quite quickly and others take more time. Regardless of the amount of time taken, the end goal of the relationship should be marriage. Likewise, some Christians may be able to make their decision to join a church rather quickly while others may take more time. Regardless of the time taken, the end goal of their search should be membership in a local church.
PDF version: The Importance of Church Membership