To answer your first question, Yes, “for the gifts and the call of God are irrevocable” (Rom 11:29) and He said of the Jewish people:
- “Now therefore, if you will obey my voice and keep my covenant, you shall be my own possession among all peoples; for all the earth is mine, and you shall be to me a kingdom of priests and a holy nation.” (Exo 19:5-6)
- “For you are a people holy to the LORD your God; the LORD your God has chosen you to be a people for his own possession, out of all the peoples that are on the face of the earth.” (Deut 7:6)
However, this does not mean that it is acceptable for them to explicitly reject the divinity of Jesus Christ and the New Covenant that He established. This covenant in His Blood fulfills everything that the Jewish people had previously received, and adds to the number of the “chosen people” anyone who has faith in Christ and is baptized. That is why St. Peter says that the Church has now become what the Jews always were:
“But you are a chosen race, a royal priesthood, a holy nation, God's own people, that you may declare the wonderful deeds of him who called you out of darkness into his marvelous light” (1 Pet 2:9).
The Church is now the place where Jew and Greek, slave and free, man and woman can come and experience God’s saving power (cf. Rom 10:12; Gal 3:28; Col 3:11). Unfortunately, the Jews, while undoubtedly God’s chosen people, are people who are disobedient to this new covenant and its realization in the Church.
Fortunately, God is not through with the Jewish people yet. The Bible tells us that one sign that the End Times are upon us will be the mass conversion of the Jewish people to Christ and the New Covenant:
- “And I will pour out on the house of David and the inhabitants of Jerusalem a spirit of compassion and supplication, so that, when they look on him whom they have pierced, they shall mourn for him, as one mourns for an only child, and weep bitterly over him, as one weeps over a first-born.” (Zech 12:10)
- “I will cleanse them from all the guilt of their sin against me, and I will forgive all the guilt of their sin and rebellion against me.” (Jer 33:8)
- "Lest you be wise in your own conceits, I want you to understand this mystery, brethren: a hardening has come upon part of Israel, until the full number of the Gentiles come in, and so all Israel will be saved” (Rom 11:25-26)
What a great day that will be!