We just started a preaching series on the book of I John and one of the first things the reader is struck with is the primary importance John places on fellowship within the body of Christ. We are so wired for an individual, a personal faith that the idea of expressing and growing in our faith in community is totally foreign to us. John could not empathize fellowship more - it is at the core of I John. Look at the first 7 verses (& notice all the plural pronouns)
"That which was from the beginning, which we have heard, which we have seen with our eyes, which we have looked at and our hands have touched--this we proclaim concerning the Word of life. 2 The life appeared; we have seen it and testify to it, and we proclaim to you the eternal life, which was with the Father and has appeared to us. 3 We proclaim to you what we have seen and heard, so that you also may have fellowship with us. And our fellowship is with the Father and with his Son, Jesus Christ. 4 We write this to make our joy complete.
This is the message we have heard from him and declare to you: God is light; in him there is no darkness at all. 6 If we claim to have fellowship with him yet walk in the darkness, we lie and do not live by the truth. 7 But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus, his Son, purifies us from all sin."
I thought this preaching clip from Mark Driscoll drove this point home