Tom Butler said:
... The Universal Church is a fantasy, which has no reason for existence. ...
I agree with much of your post, but disagree with some. I have to disagree here.
Matthew 16:15-8 has -- emphases mine
"I will build my church, and the gates of death will not overcome it’” (TNIV|ASV|TNIV).
Acts 2:47 examples how
“the Lord added to them day by day those |who were being saved” (ASV|NASB)
Acts 5:14 elaborates with
"believers were added to the Lord" (ESV).
The Greek word translated "church" is used similarly with regard to the community of followers of Pythagoras.* Per Acts 11:26, "Christians" is a rename of "disciples" (KJV) "followers" (ICB). The Greek translated "disciples" or "followers" is plural for "one who follows one's teachings."**
Hence, when Jesus Christ said "I will build my church" -- singular -- He was saying that He would build His ONE community of followers. The Lord does this by adding "believers" to it. All "believers" = "those who" are "being saved" are added to the Lord's "my church" -- ONE singular church.
As you aptly pointed out, this teaching gets abused by people seeking to self-excuse themselves of their obligation to assemble with other Christians. Abusing a teaching does not invalidate it. Also, taking one teaching of Scripture and using it to self-excuse oneself from a directive of Scripture is wrong.
...One day, we believers will all gather as the great General Assembly in the presence fo God. Until it does assemble, there are only local congregations, uniquely formed to carry out the Great Commission.
There are not "only local congregations" to do Christ's work here. There are also individual Christians.
Of course, for those individual Christians to be doing as they should, they should follow Hebrews 10:24-5 emphases mine
“and let us consider how to stimulate one another to love and good deeds, |not giving up| our own assembling together, as is the habit of some, but encouraging one another, and all the more as you see the day drawing near” (NASB|TNIV|NASB).
The purpose of such assembly is "let us consider how to stimulate one another to love and good deeds" and reiterated with "encouraging one another."
The New Testament-era Christians did that. The only exception recorded in Scripture is the Ethiopian official of Acts 8, because his regular life had him going away from established congregations. For the rest of the New Testament, we see such things as "the church at __." Portions of the church were getting together in various localities. This practice started with the very first Christians at Jerusalem in Acts 2.
To be doing what we should in the `universal church,' we should be assembling ourselves together with a local group of believers.
___________
*Arndt, Gingrich, et al, A Greek-English Lexicon of the New Testament and Other Early Christian Literature, page 240.
**Vine, et al, Vine’s Complete Expository Dictionary, page 171 NT.[/QUOTE]