You are right, you didn't say Universal Church. Are you drawing a distinction between the Church and the Universal Church? If the Universal Church is not this:, then would you give your definition?
There is a local body of believers which is called the church. Those who are redeemed are redeemed only by the shed blood of Jesus Christ. The term Church is also used to refer to the total number of the redeemed. In the Scripture I posted the Church, as the total number of the redeemed is called the Bride of Jesus Christ. You are free to accept this truth or not.
Now, to Ephesians 5:25-27. Paul is speaking in a generic sense when referring to the husband and wife. Because in reality, it takes a real individual husband to love a real individual wife. And a real Christ to love a real individual church. And Paul also spoke of the church in a prospective sense, but no church--local or universal--is today without spot or blemish.
Ephesians 5:27-28
25. Husbands, love your wives, even as Christ also loved the church, and gave himself for it;
26. That he might sanctify and cleanse it with the washing of water by the word,
27. That he might present it to himself a glorious church, not having spot, or wrinkle, or any such thing; but that it should be holy and without blemish.
It is nonsense to argue that Paul is speaking of a local church. Jesus Christ died for all the redeemed of all time and that is the analogy that Paul is using here, husbands are to love their wives as Jesus Christ loved the Church. No one is saying that the Church at this time, the total number of the redeemed, is without
spot, or wrinkle, or any such thing, not even Paul. It simply states that Jesus Christ will present the Church to himself:
a glorious church, not having spot, or wrinkle, or any such thing; but that it should be holy and without blemish. That will happen when Jesus Christ returns at the end of time as we know it. All one need do to understand this is to read Revelation 21 and 22 without the use of dispensational filters!
But it will be when the great General Assembly gathers in Heaven. At that point, there will be no more local congregations, for we will all be unified, finally knowing the truth.
You are correct as far as you go. At this point the Church, the Bride of Jesus Christ, will be perfect. But you need to look at the entire passage:
Hebrews 12:22-24
22. But ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels,
23. To the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the spirits of just men made perfect,
24. And to Jesus the mediator of the new covenant, and to the blood of sprinkling, that speaketh better things than that of Abel.
Notice that the passage uses the terms: mount Sion, city of the living GOD, the heavenly Jerusalem, the general assembly and church of the first born. All of these are terms used to describe the Church, just as the terms holy city, New Jerusalem, and Bride of the Lamb are used in Revelations 21.
With regard to Acts 20:28, let's remember that Paul was in Miletus, and called the elders to him from their congregation at Ephesus. He counseled the elders to take heed over all the flock (at Ephesus),
the one over which the Holy Spirit had made them overseers (at Ephesus).
He told the feed the Church of God (at Ephesus, over which he had made them overseers), which (obviously Jesus) he had purchased with his own blood.
Notice that Paul did not say feed the churches of God for which Jesus Christ died but feed the CHURCH [ that is singular not plural]. Can you guarantee there was only one congregation at Ephesus since there were many pastors/preachers? Who did Jesus Christ purchase with His blood? Everyone who has been or will be redeemed.
What would you say is the reason for the existence of the Church as you understand the definition of Church? And what commission does it carry out that the local church does not or cannot?
What is the reason for the existence of the Church? Consider Acts 2:46, 47
46. And they, continuing daily with one accord in the temple, and breaking bread from house to house, did eat their meat with gladness and singleness of heart,
47. Praising God, and having favour with all the people. And the Lord added to the church daily such as should be saved.
Also consider John's admonition to the Church at Ephesus:
Revelation 2:1-5
1. Unto the angel of the church of Ephesus write; These things saith he that holdeth the seven stars in his right hand, who walketh in the midst of the seven golden candlesticks;
2. I know thy works, and thy labour, and thy patience, and how thou canst not bear them which are evil: and thou hast tried them which say they are apostles, and are not, and hast found them liars:
3. And hast borne, and hast patience, and for my name’s sake hast laboured, and hast not fainted.
4. Nevertheless I have somewhat against thee, because thou hast left thy first love.
5. Remember therefore from whence thou art fallen, and repent, and do the first works; or else I will come unto thee quickly, and will remove thy candlestick out of his place, except thou repent.
This church might be called the perfect church but they had one fault. They had left their first love. What or who was their first love? Jesus Christ!
The first duty of the believer and the body of believers is to praise, glorify, and worship their GOD and Savior. All else is secondary. the church at Ephesus had got so busy being an organization they had forgotten their primary purpose and were chastened for that.
Since Jesus Christ is not polygamous HE has only one BRIDE. I use the term Church to include the total number of the redeemed, for whom Scripture states HE died, for whom HE shed HIS blood. That shed blood is the only means for redemption of anyone, nothing else will suffice. I generally use the term church when speaking of the local body of believers.