This passage of Matthew 23.37-39, contains three distinct prophecies from our Lord Jesus Christ. Two (His rejection by Jewish Jerusalem, and His abandonment of the city and its Temple to destruction and ruin) have already been plainly, and before the eyes of the whole world, fulfilled. The third will likewise be effected. But this will take place in the midst of horrendous, catastrophic conflict (which has been foreshadowed in WW2 and the Holocaust).
At the root of this lies (not only murderous, demonic anti-Semitism) but also "the prince of this world's" utter and complete hatred of the true King. (1) Jesus' enthronement means the devil's dethronement...and he will fight for his own existence, caring for the existence of no one else, not even God! This is no light matter to be addressed by a couple of cutesy-pie choruses, a franchised message, and a pot-luck dinner. It will require a revolution of and in the Church, according to Matthew 21.13, Mark 11.17 and Luke 19.46.
Israel's very existence is again about to be contested and threatened to the uttermost...and with her, existence itself on earth! "How can this possibly be?" I hear you dry-mouthedly enquire.
In the 1930s, a singular, Reformed theologian in Germany went toe-to-toe with the "antichrist" Hitler. His name was Karl Barth (1886-1968). Reflecting later upon this awful (and extremely prophetic) period of history, he wrote (2) that any denial of Israel was "a denial of Jesus Christ and therefore finally, of God Himself...The man who is ashamed of Israel, is ashamed of Jesus Christ and therefore of his own existence."
At present, among those who are sympathetic and supportive of God's Jewish People and the State of Israel, there is a call for the Church to return to its "Jewish Roots"? If this means anything other than a renewed cleaving unto Jesus Himself as the true root of the ancient Olive Tree (into which we "wild olive" shoots have been "grafted" - Ro 11) then the call is bunkum and hocus-pocus.
"If the root is holy, so are the branches." (Ro 11.16)
"The root of Jesse shall come, he who rises to rule the Gentiles; in him shall the Gentiles hope." (Ro 15.12)
"Weep not; lo, the Lion of the tribe of Judah, the Root of David, has conquered." (Rev 5.5)
"I Jesus...am the root and the offspring of David, the bright morning star." (Rev 22.16)
This biblically famed picture of the Olive Tree-Israel-Church, commands Christian love for the Jewish People, ancient and modern. Why? Because they have only ever existed, and exist today, upheld in His Covenant with Abraham, by the Root who "is the same yesterday and today and for ever." (Jn 8.58, Heb 13.8)