We are transformed one at a time, but we are not transformed alone. We are transformed in groups. If you are not in a group that is working toward being transformed into the image of Christ, you will not be transformed. People are not transformed alone. The writer of Hebrews made this clear:
And let us consider how we may spur one another on toward love and good deeds, not giving up meeting together, as some are in the habit of doing, but encouraging one another—and all the more as you see the Day approaching. Hebrews 10:24–25 (NIV2011)
This verse is often used as an admonition to come to church. Note that this is not what it is talking about. It is not talking about sitting in straight rows and watching the same events happen on the same stage. It is talking about meetings where we encourage one another; meetings where I encourage you and you encourage me. As Andy Stanley says it, “Circles are better than rows.”
Circles encourage one another to start their day with the Bible on their lap. Circles rejoice with those who rejoice and weep with those who weep. Circles ask hard questions. Circles probe. Circles admonish. Circles hug. Circles love.
You can’t get there alone. Scaling the mountain of spiritual maturity is like scaling the physical Mount Everest. No one gets there alone:
For each level that the climbers reached, a higher degree of teamwork was required. One set of men would exhaust themselves just to get equipment up the mountain for the next group. Two-man teams would work their way up the mountain, finding a path, cutting steps, securing ropes. And then they would be done, having spent themselves to make the next leg of the climb possible for another team. Of the teamwork involved, Tenzing remarked, “You do not climb a mountain like Everest by trying to race ahead on your own, or by competing with your comrades. You do it slowly and carefully, by unselfish teamwork. Certainly I wanted to reach the top myself; it was the thing I had dreamed of all my life. But if the lot fell to someone else I would take it like a man, and not a crybaby. For that is the mountain way.”
You can’t get there alone. You can’t become a disciple alone. You can’t do this alone. Look at this verse and consider carefully what it teaches about how we grow. (You will likely learn more from your reflection on Scripture than your reading of my comments.)
Instead, speaking the truth in love, we will grow to become in every respect the mature body of him who is the head, that is, Christ. From him the whole body, joined and held together by every supporting ligament, grows and builds itself up in love, as each part does its work. Ephesians 4:15–16 (NIV2011)
First, Paul says we grow by speaking. This is surprising to me. I would have expected this verse to say, “Hearing the truth, we will grow…” That is not what he says. Paul says we grow by speaking the truth in love.
We are changed more by what we say than what we hear. Hearing is important. “Faith comes by hearing…” (Romans 10.17) But, hearing is not as important as speaking. Jesus said it is what comes out of the mouth that defiles us. (Matthew 15.28) James taught that the words we speak are like the rudder on a ship. I think if he were speaking today, he would say that the words we speak are like the steering wheel of our lives.
People who speak words of gratitude develop grateful hearts. People who speaks words of love become more loving. People who grumble and complain become more grumpy and negative. We are changed more by what we say than what we hear. More on this later.
This passage also teaches that we grow as we are joined and held together by every supporting ligament. I am not sure what a supporting ligament is. I think that is the point. The body grows as it is held together by obscure parts that no one knows about. Little people matter in the body of Christ. They are part of what makes us connected. Francis Schaffer talks about this in No Little People:
We must remember throughout our lives that in God’s sight there are no little people and no little places. Only one thing is important: to be consecrated persons in God’s place for us, at each moment. Those who think of themselves as little people in little places, if committed to Christ and living under His Lordship in the whole of life, may, by God’s grace, change the flow of our generation.
Verse 16 says the parts of the body are joined. The word pictures rocks that are fitted together to make the wall of a building. It is an obscure word, used only twice in the New Testament, here and in Ephesians 2.21.
In him the whole building is joined together and rises to become a holy temple in the Lord. Ephesians 2:21 (NIV2011)
We are not only joined, but held together. This too is an unusual word, used only seven times in the New Testament. The NIV translates it six different ways, which tells you it is a bit difficult to translate. This word means “to bring together,” “to reconcile,” and in philosophy “to compare,” “to infer,” “to show,” and finally “to expound.”
I am not sure Paul means anything different by using this second word so much as the layering of words brings emphasis to the central idea: you can’t grow alone. You can’t be transformed in isolation. We only grow in a group. We only grow in circles. The second word above is also used in Colossians:
They have lost connection with the head, from whom the whole body, supported and held together by its ligaments and sinews, grows as God causes it to grow. Colossians 2:19 (NIV2011)
We see a similar idea in this verse, although the metaphor is different. Rather than picturing a building, as in Ephesians 2.21, we are invited to see a body. (Similar to Ephesians 4.16 above.) Again the body is connected by parts that no one sees. There are not little people. The people on the stage are not the most important ones in the body of Christ. The worker rocking crying babies matters just as much.
There is one more word in this verse I would like us to look at, the word translated supported. One Greek dictionary says, “to make available whatever is necessary to help or supply the needs of someone—’to provide for, to support, to supply the needs of, provision, support.’” 
Note the phrase, “whatever is necessary.” We grow as each person has the attitude of giving to one another whatever is necessary to grow. If people need encouragement, I will encourage. If they need love, I will love. If they need correction, I will correct. I will not do just what is convenient or what I am in the mood to give. I will give whatever it takes for the body to grow.
 John C. Maxwell, Teamwork Makes the Dream Work (Nashville: Thomas Nelson, 2002).
 Francis A. Schaeffer and Udo Middelmann, No Little People (Wheaton, IL: Crossway, 1974).
 Gerhard Kittel, Gerhard Friedrich, and Geoffrey William Bromiley, Theological Dictionary of the New Testament (Grand Rapids, MI: W.B. Eerdmans, 1985), 1101.
 Johannes P. Louw and Eugene Albert Nida, Greek-English Lexicon of the New Testament: Based on Semantic Domains (New York: United Bible Societies, 1996), 460–461.
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