This is a common misconception among Western Christianity, in that what is translated today as "church" in English translations of the Bible, I fully understand the lack of knowledge among those here in the West who are products of Western thinking and the influences from replacement theology. Here's a source that perhaps you will listen to. If not, then perhaps I can find one you do respect and admire. This is from Ligonier:
"God promised Abraham’s grandson Jacob that He would make his twelve sons into a harmonious worshipping “community of nations” (
Gen. 28:3) that would be known by his new name, “Israel.” Significantly, the Hebrew word used here for “community” is
qāhāl, which the Greek translation of the Old Testament often renders as
ekklēsia, “church.”" (
https://www.ligonier.org/learn/articles/the-church-and-israel-in-the-old-testament)
The Apostle John, who also was a Jew and under inspiration, had no problem calling the Jewish congregations in those seven cities "the church in..." Congregation, group, collection...church. Israel also was a "church" in ancient times, and once the northern ten tribes were scattered in about 752 BC, they were scattered into the very areas that were later recipients of the seven letters written by John by inspiration.
Contrary to modern, Western thought that is so greatly influenced by replacement theology, God still has a purpose for the ethnic nation Israel. If that were not the case, then any promise the Lord made to anyone would be subject to question and change at God's whims. He is not so fickle, as many modern-day theologies lead anyone to surmise dare they carry those doctrines to their logical conclusions. Spewing the lukewarm from His mouth does not and cannot refer to those of us who are sealed by Holy Spirit. The belief in loss of salvation is utterly false, lest one is prepared to defend the idea that Holy Spirit has a weak seal, or grasp, which would include Jesus Himself who also declared that there is no power in Heaven or earth that can snatch even one from His Hands.
I do not believe the apostles were any less sealed by Holy Spirit once they came to the knowledge and understanding of the Gospel of Grace. This leads into your next quandary:
Hope all is well with you and yours through that storm.
Please pay close attention to the ELEMENTS within the two different gospel messages preached by Peter and Paul.
Peter preached this:
Acts 2:37-38
37 Now when they heard [this],
they were pricked in their heart, and said unto Peter and to the rest of the apostles, Men and brethren, what shall we do?
38 Then Peter said unto them,
Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.
Paul preached this:
1 Corinthians 15:1-4
1 Moreover, brethren,
I declare unto you the gospel which I preached unto you, which also ye have received, and wherein ye stand;
2
By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain.
3 For
I delivered unto you first of all that which I also received, how that
Christ died for our sins according to the scriptures;
4 And that
he was buried, and that
he rose again the third day according to the scriptures:
Notice also that Christ, in all His preaching and what He taught the disciples to preach, never once included the projection of His death, burial and resurrection on the third day. The disciples had no understanding of what He meant when He revealed to them that he was going to suffer, and they were afraid to even ask. They were expecting Him to become King and to establish His Kingdom, for He preached that the Kingdom was AT HAND. That's not at all a message hinting at yet another 2000 years into the future.
There is very good reason as to why the prophetic program was put on hold, but that is a much longer discussion and involves study on your part to glean the background from the OT and NT as to why it happened as it did. The Lord had His own way of revealing that without coming right out and declaring it in a fashion that meets with the subjective demands of some out there who want it all to fall into their laps on a silver platter. I'm not saying you are of that caliber, but there are those who reject all this blindly because they're too lazy to search out the scriptures to see if it's true. Some things simply require deeper study, like Gold that must be mined deep from within the earth to acquire, such as in the gold rush days.
Hope this helps.
MM