The local church is the hope of the world. These are not originally my words—I stole them from the founder and well-known preacher from Willow Creek, Bill Hybels. He honestly believes that the local church is the engine with which the message of the gospel will be spread to the world. And I believe he is right.
Early Christianity spent much of its time attempting to work out what they believed about Jesus, the nature of the Trinity, and how to deal with those who felt differently than what was decidedly orthodox. Thus, when you read the early creeds there is a lot of focus on the Godhead, and less focus on other things like the church.
Nevertheless, the Apostles Creed clearly states, “I believe in the holy catholic church.” Not catholic in the organizational sense (i.e., Roman Catholic) but catholic in the sense of universal. Denomination, ethnicity, age, or status does not matter—those whose faith is in Jesus Christ alone are members of the church. They are the ones “called out” (which is the Greek meaning of ecclesia, or church) to a new way of life together. We are united together in our faith.
Thus, participation in a local church is a necessary aspect of your faith. I participated in the local church before I was a minister and I participated in the local church during my 9-month transition period between ministry positions. I am a local church member because it is good for my faith, my theology, because Scripture teaches that I ought to gather, and because the local church is the hope of the world.
Theology: Orthodoxy is best determined in the company of the local church. We need to look only to the book of Acts to see how theology is derived in community, not in isolation. When the Jews and Gentiles were having disputes about what needed to be done in the flesh to gain entry into the Kingdom of God, the local church overseers took their views to the overseers in Jerusalem. Many people gathered over several days at this first church council to discuss what was an appropriate understanding of this matter. Over time they were able to come to an agreement that seemed good to them and to the Holy Spirit, and they wrote a letter to the churches conveying their findings. Theology is best derived in the community of the local church where there is diversity of thought and the presence of all of the gifts that God has left to his church (Eph 4, 1 Cor. 12-14), not just the few that are present among our group of friends.
Spiritual Covering: Think of the local church as a place that provides fences or boundaries to our spiritual lives. Scriptures teaches that on our own we have a propensity toward sinfulness. Therefore, standing alone makes us far more vulnerable to fine sounding deception from the enemy. The first thing the enemy will do to an isolated Christian is affirm their distrust of the local church. Despite our North American individualism, we need each other in Christian community to mount a spiritual offensive on our behalf. Think of an army metaphor—there is a reason soldiers move in groups. It is for their protection. We need the spiritual covering (and protection) of the local church.
Diversity: Now, you might still be inclined to tell me that theology and spiritual covering can be obtained in the company of a group of friends outside of the local church. What you are describing, however, is a small group and not an expression of the local church. Here is why: the local church contains not only those people that you like, but also those people that you need. We gather in small groups with friends because we find comfort and security in that. We gather with the local church because the diversity of people present challenges us to grow in character and in our understanding and experience of God. God places broken and perhaps annoying people in our path to expand our expression of love and humility.
If this has challenged you about your involvement with the local church, I encourage you to re-read the New Testament, especially the parts about unity among Christians, not ceasing to gather together, and submitting to the authorities that God has put in place. Finally, no matter how you feel about the local church in your community, do not talk bad about it—it is the bride of Christ. God is the judge over all that he created and he will right all wrongs some approaching day, not us.
Therefore, participate in your local church—it is the hope of the world.