An old theory persists, whose origins are disputed, but that continues to be believed by many, according to which the church of Christ is a sequel of Israel, and all promises and promised blessings to the patriarchs, and to Moses, Joshua and David, were transferred to the church, being “spiritualized” when they involve terrestrial things. It is known as the Theology of Substitution. The upholders of this theology believe - and teach - that God has no more specific plans for the nation of Israel.
On the basis of that theory, some churches have been closing their eyes to oppression of Jews, and, when allied to the public power, they have even promoted cruel persecutions themselves. Jews keep remembering such harassments, and generalize the concept of enemies to all Christians.
As the Bible is very clear on this subject, and distinguishes perfectly between the church and Israel, it is surprising that there are still churches today teaching that there was substitution, which is an impairment to a better understanding of what the Bible teaches, of a great part of the prophecies of the Old Testament, and of some of the New, that are abandoned as being of “difficult interpretation”. That is natural, because they should be accepted literally and not “interpreted spiritually”.
For instance, the prophecies of the Bible concerning the blessing and restoration of Israel to the Promised Land are “spiritualized”, assuming that they are just allegories of promises by God to the church. The main problem with this vision now is the continuous existence of Jews along the centuries and especially the revival of their nation in the modern State of Israel. If Israel had really been condemned by God, and there was not future for the Jewish nation, how can it explain the supernatural survival of the Jews during the last 2000 years, in spite of so many attempts to destroy them? How to explain why and how Israel reappeared as a nation after disappearing for nineteen centuries?
The fact that Israel and the church are different is taught clearly in the New Testament. Speaking biblically, the church is completely different and separate from Israel and the two can never be confused or exchanged. The Bible teaches that the church is a completely new creation, a mystery hidden in the Old Testament and only revealed in the New, that it began to exist on the day of Pentecost after the death, resurrection and ascension of the Lord Jesus, the Messiah promised to Israel, and that it will continue on earth until its rapture to heaven by Him (Ephesians 1:9-11; 1 Thessalonians 4:13-17). The church has nothing to do with the curses and blessings for Israel. The pacts, promises and warnings of the Old Testament are only valid for Israel. Israel was put temporarily to the side in the program of God for these last two millennia of dispersion.
After the rapture of the church (1 Thessalonians 4:13-18), God will focus again on Israel in the execution of His plan for the world. For seven years God will spill His anger on the world for rejecting Christ, which the Bible calls “The Day of the Lord”, or the Tribulation (Revelation chapters 6 to 19). Meanwhile Israel will be prepared for the Messiah's second coming, by preaching and conversion to the Gospel followed by the trials of the Great Tribulation that will happen in the second half of those seven years.
The situation in antiquity, before the beginning of the church, at the present time and in the future it is commented on in chapters 9 to 11 of Romans, from where the following is extracted:
The Israelites were privileged, adopted by God, He gave them glory, covenants, legislation, the worship and the promises; from them come the patriarchs and of them descends Christ who is Lord of all and blessed God forever and ever. God is sovereign, he chooses who He wants to favour, and He determines the place of each one. We are not entitled to criticize His decision, because He is the Creator of everything.
God endures malefactors with a lot of patience, though prepared for destruction, in order to show His anger, to make known His power, and to reveal the riches of His glory on the vessels of mercy, prepared beforehand for glory, which embraces all of us, Jews and Gentiles.
God calls people of the Jews and of the Gentiles also, to be vessels of His mercy, as announced through the prophet Hosea (1:9-10) and prophet Isaiah (10:22-23).
Of the children of Israel only the remainder will be saved, no matter how much they grow, and this will come true, completely and soon. As Isaiah also prophesied (1:9), if the Lord of the Armies had not preserved descendants of the Jews, they would already have disappeared.
Israel seek justification based on obedience of the law, and don't attain the law of righteousness because they seek it by works and not by faith. Israel reject Christ's redeeming work: the “stumbling stone and rock of offense” prophesied in Isaiah 28:16.
All (be they Jewish or Gentiles) that call on the name of the Lord shall be saved (Joel 2:32). Not all obey the word of the Gospel, as prophesied in Isaiah 53:1, although the voice of God is heard in the whole world, according to Psalm 19:4. Many Jews are being saved by the election of grace, in other words, by the faith in Christ, as happened with the apostle Paul himself. As in the time of Elijah God reserved for Himself seven thousand men that didn't worship the image of Baal, likewise in this current time a minority survives for the election of grace. The others, that seek to justify themselves by the works of the law, will not get it, and will remain spiritually deaf and blind.
Most of the people of Israel will continue in their incredulity until the fullness of the Gentiles has come in (the church of Christ will have been completed, those alive having been taken to be with Him in His presence), but after that the whole remaining Israel will be saved, on the return of the Lord, as prophesied in Isaiah 59:20-21. The place of privilege before God, symbolized by an olive tree, was first occupied by the Jews; most of the nation of Israel was rejected for their incredulity (broken branches), while the Gentiles (wild olive tree) believers were admitted (grafted in the olive tree) to the grace of God by faith, participating in the blessings that come from Abraham to whom God said: "in you all the families of the earth shall be blessed" - Genesis 12:3 (root and fatness of the olive tree).
But the Gentiles should not despise the Jews: just as God rejected the Jews, as a nation, for their unbelief and received the Gentiles because of their faith, so He will reject the Gentiles if they don't remain in God and will accept the Jews again, as a nation, if they leave their unbelief. It is more natural for the nation of the Jews to adjust to the kingdom of God when it believes, because of their root in Israel, than for the Gentiles, that come from outside. "Gentiles" here doesn't mean the Church, or some believer in particular. We have in this whole chapter the people of Israel on one side, and the other people, the Gentiles, on the other. Christ's Body will never be able to be separate from Christ, that is the Head, nor can a believer be separated from the love of God. But the Gentiles can, according to his verse, lose the privileged position that they enjoy today.
The remainder of Israel that survive tribulation will then be in a condition to receive the Messiah, and Christ will return to earth, putting an end to the Great Tribulation and liberating Israel from the powerful enemies that surround them. He will establish His kingdom as the King of kings on earth having Jerusalem as His capital. Israel will be the main nation, and the nations that have treated well the Jews during their tribulation will survive (Matthew 25:31 to 40). The representatives of all those nations will come to Jerusalem to honour and to worship the divine King. The members of His church will have returned with Him, in their immortal bodies, literally to reign with Him in the millennium (Revelation 20:1-5).
Then will the prophecy be fulfilled: “it shall come to pass in the latter days that the mountain of the LORD's house shall be established on the top of the mountains, and shall be exalted above the hills; and all nations shall flow to it. Many people shall come and say, ‘Come, and let us go up to the mountain of the LORD, to the house of the God of Jacob; He will teach us His ways, and we shall walk in His paths.’ For out of Zion shall go forth the law, and the word of the LORD from Jerusalem.” (Isaiah 2:2-4).