Here are some excerpts from a publication by Witness Lee :
In the Bible, God only revealed to us two ministries, one of the Old Testament or the old covenant, and one of the New Testament or the new covenant. Actually, these two ministries are one, just as the Old Testament and the New Testament are one Bible with two parts or two sections.
.......In the Old Testament there was a ministry for the preparation of the New Testament economy. Actually, the Old Testament ministry and the New Testament ministry are one. The Old Testament ministry was a preparation, a shadow, a prefigure, and the New Testament ministry is the fulfillment. What took place in the Old Testament was a shadow of what would take place in the New Testament ministry. Therefore, the New Testament ministry is the very fulfillment of the Old Testament ministry.
I am burdened to stress this point of the oneness of the ministry because of all the divisions and confusions that have taken place in the past centuries among the Christians. The most damaging thing among the Christians is the divisions and the confusions. Moreover, all the divisions and confusions came out of one source, and that source is the different ministries.
.......Christ and the church are the central subject of the entire Bible. This is the center, the focus, and also the circumference of God’s economy. Christ and the church must be everything in God’s economy. To carry out this economy, God has only one ministry, a unique ministry.
Why is it that there were divisions even from the time while the apostles, including Paul and John, were still here on this earth?
........We need to be very clear that the foundation of all the denominations and the factor that produces each denomination are their different ministries. If all the Christians today would be willing for the Lord to take away their different ministries, they would all be one. The basic factor of all the divisions, their very root, is different ministries. Ministries that are different may be very sound, even very scriptural, but they are something Paul said was creeping in at the time of Galatians 2 (v. 4, lit.). This thing crept in as early as the time of Paul. Paul, Peter, and James were all there, and a ministry of another kind was trying to come in. In 1 Timothy 1 Paul charged Timothy to remain in Ephesus to take care of one thing: to charge certain ones not to teach differently, which means not to teach according to another ministry (vv. 3-4). At that time the different teaching was the teaching of the law. In Galatians 2 what was trying to creep in was the law.
At a later time, the heretical teaching of Gnosticism came in. Gnosticism was heresy, but you cannot say that to teach something of the Old Testament was heretical.
......All of us today need to be on the alert. We need to realize that Satan could use any one of us to bring in some other kind of teaching that may be scriptural. At Paul’s time it could not be considered heretical to teach the law according to the Old Testament. The law had been given by God and unveiled by God. If I had been there teaching Gnosticism, then I would have been a heretic. On the other hand, if I had been there teaching the law of Moses, no one could have said that my teaching was heretical. In fact, the law of Moses was scriptural. Nevertheless, such teaching would have been different from the teaching concerning God’s economy as it was presented by Paul. We need to be very careful because Satan is subtle. All of us need to be alert not only to watch over others but to watch over ourselves.
If you are interested to read further, then please go to Living Stream Ministry and click on "Selected Titles by Witness Lee " which is on the left colum, then select publication No. 136 : Elders Training Book 01: The Ministry of the New Testament. I am not able to get you directly into the link unfortunately.
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