True, Philip did need to assist the eunuch to explain who Jesus is, but i believe that is still the job of every believer, no matter how clumsy they may be, the HS will honor it if the scriptures are presented. I don’t think one needs a perfect understanding of all things in the bible to be saved, nor does one need “perfect and complete” knowledge to be a witness.Note please that the Samaritan woman at Jacobs well in Jn. CH.4 did not have credentials from any church, yet she went just after she was saved to be a witness for Christ and I believe many in her village also believed on Jesus because of her and the witness of the HS.
I do understand about Paul’s vision of “oneness” in Philippians, however he says in ch.1:18 “notwithstanding, EVERY WAY, whether in pretence or in truth, Christ is preached; and I therein do rejoice, yea and do rejoice.” You see, that unlike some, Paul rejoiced in whatever way the gospel was preached as long as someone was doing it.
Having checked out the modern versions, i see that you are right about my quote from Peter.The “the” in KJV has been replaced with “a”, which does indeed change the meaning. Thank you for pointing that out.
I don’t think anyone has a “complete and accurate” knowledge of the Bible. Yet, one must get some things right. The bible says in James 1:5 “If any of you lack wisdom, let him ask of God, that giveth to all men liberally”. Have you not ever asked the HS to show you the meaning of a scripture? He is able and willing. Often, in meditation He will illuminate a verse without my even asking.
I can evangelise along side a Reform believer without a problem because we all believe the same in regard to the basic Gospel. The power of the Gospel is not hindered. Just as in Mt. 16:15, it is the HS who must bring the revelation of who Jesus is.
I think that it is that I have a different definition of the meaning of “church” than you. As you know, the Greek is “ekklesia” which is rendered from two root words: “ek”, meaning “out of, from, by, or away from” and “kaleo” meaning “to call aloud or to invite”. Thus the basic meaning is "the called out or the called out ones or assembly. It is not an hierarchical organization in what I see, but obviously your tradition sees differently, but I hope you will allow that the Kingdom of God can still work even if it is done according to the plain meaning of the text. Sometimes less is more.