Paul’s use of the words “being built up” in 2:7 do not refer in a direct way to the building up of the Body of Christ. Rather, this expression denotes an increase in our spiritual stature, which can be compared to a person’s increase in stature as he grows physically. The only way a child can grow physically is by assimilating nourishing food. In the same way, we grow spiritually by assimilating the rich nourishment of Christ. This is what it means to be built up in Christ, as mentioned in 2:7. First Paul tells us that we have been rooted in Christ. Then he goes on to say that we are being built up in Christ. No tree can grow up without first being rooted. The growing up of the tree is also the building up of the tree.
If we are lacking in spiritual stature, it is of no avail to speak of the building up of the Body. In Ephesians 4:13 Paul says, “Until we all arrive at the oneness of the faith and of the full knowledge of the Son of God, at a full-grown man, at the measure of the stature of the fullness of Christ.” The Body of Christ has a stature, and this stature has a full measure. We all need to grow until we arrive at the full measure of the stature of the Body of Christ. For us to be built up does not first mean that we are built up as the church, the Body. It means that we are built up in the Lord and experience an increase of stature. Hence, in Colossians 2:7 to be built up actually means to grow up. First we are rooted into Christ as the all-inclusive Spirit, and then we grow up in Him. We build ourselves up by growing up. Our being built up depends on our assimilating into our being the riches of Christ as the soil. Having assimilated these riches into us, we shall grow and be built up. When we are fully grown, we shall be built up. Therefore, to be built up simply means to grow up. In order to grow, we need nourishment. Our growth depends on how much nourishment we assimilate into us by being rooted in Christ. Because we are rooted in Him, we absorb into us the riches of the all-inclusive Spirit. Then we grow with the nourishment we derive from these riches.
According to 2:19, by holding the Head we grow with the growth of God. Out from the Head, the Body grows with the growth of God. God here is the processed Triune God, as in Matthew 28:19. Out from the processed Triune God as our source, the Body grows by absorbing the riches from the Head. The Body does not grow with biblical knowledge, but grows with the growth of God. In Himself, God is infinite, perfect, and complete. Therefore, in Himself God cannot grow. But in us God can grow and He needs to grow. We grow by the growth of God in us. Because we have so little of the Triune God within us, we need the addition of God for our spiritual growth. We grow with what we absorb from the Head.
The vital and crucial point is that we grow by absorbing the riches of Christ. In order to absorb His riches, we must be rooted into Him as the all-inclusive Spirit. Remember that this Spirit dwells in our spirit. The soil is not our mind, emotion, or will; it is the all-inclusive, processed Triune God dwelling in our spirit. The source of the riches we need for our growth is the processed Triune God in our spirit. Just as we go to a faucet to get water, so we must turn to our spirit to get the riches of the Triune God.
In order to become more deeply rooted into the processed Triune God, we need to exercise our spirit, not our mind, emotion, or will. However, our environment does not favor the exercise of the spirit. On the contrary, everything in our environment works to keep us away from the spirit. For example, throughout most of the Lord’s Day, a brother’s wife may be very pleasant to him. But just before the Lord’s table meeting, she may speak an unkind word to him. In his reaction to her unkindness, he is immediately drawn away from the spirit. In the midst of such a situation, the brother needs to exercise his spirit and call on the name of the Lord Jesus. By this exercise of the spirit, he will become more deeply rooted into Christ as the soil and automatically absorb more of the riches of the all-inclusive Spirit. This will produce more growth.
We need to continually exercise our spirit. This is the reason that toward the end of the book of Colossians, Paul charges us to persevere in prayer (4:2). However, if, instead of exercising our spirit, we exercise our mind, emotion, and will, Satan will keep us from enjoying the all-inclusive Spirit in our spirit. Satan, the subtle, evil one, uses the environment to keep us out of the spirit. Thus, we need to exercise our spirit continually by calling on the name of the Lord in order to become more deeply rooted into the all-inclusive Spirit. Then we shall absorb the riches of Christ, grow in Christ, and spontaneously be built up in Christ. As a result, we shall walk in Him. If we understand this, we shall know what it means to walk in Christ by absorbing His riches and by being built up with what we have absorbed. This is the practical experience of Christ we all need.