Then, the words "Christian" and "nation" have no meaning.
In today's world...NO! they do not. What is the definition of a "Christian" from the biblical point of view, as opposed to man's ideas about what constitutes a genuine "Christian" in these last days? What "nation" are the scriptures alluding to when it speaks of those who will replace the nation of Israel? It is no worldly nation. Jesus said that his Kingdom is not of this world.
To the wicked Jewish leaders....
"Jesus said to them: “Did you never read in the Scriptures, ‘The stone that the builders rejected, this has become the chief cornerstone. This has come from Jehovah, and it is marvelous in our eyes’? 43 This is why I say to you, the Kingdom of God will be taken from you and be given to a nation producing its fruits. 44 Also, the person falling on this stone will be shattered. As for anyone on whom it falls, it will crush him.”
45 When the chief priests and the Pharisees heard his illustrations, they knew that he was speaking about them. 46 Although they wanted to seize him, they feared the crowds, because these regarded him as a prophet." (Matthew 21:42-46)
If God says he is not partial concerning what nation or language we are, (Acts 10:34-35) then there is no "nation" on earth who can claim to be of that nation simply by birth as Israel was. The "Israel of God" (Gal 6:16) Paul identified as consisting of both Jewish and Gentile Christians from all nations.
Literal Israel was "abandoned" by God a long time ago because they could never uphold their part of God's covenant with them. Jehovah had the right to terminate their legal agreement on those grounds, but he kept Israel in existence until his part of the covenant was fulfilled. He replaced those who failed to obey him with those who would obey, not only their God and his written word, but also to accept his Christ.
In Devotional Reading today 1 Peter 2:9 NRSV says
we are a chosen race of people, which is tied being spiritual off spring of Abraham.
Israel is a nation.
What Does the Bible Say about the Modern Nation of Israel?
Who is "we"?
The fleshly nation of Israel were abandoned by God who, throughout their pathetic history, demonstrated that they were exactly as God described them....a stiff-necked, disobedient and rebellious people, whom he had wanted to exterminate at times when they left off from serving him to turn to false gods and religious practices. Even God’s own chosen nation proved that humans cannot serve God for long under the rulership of flawed human kings.
Jesus passed judgment on them and their self righteous religious leaders....
Matthew 23:37-39...NLT...
“O Jerusalem, Jerusalem, the city that kills the prophets and stones God’s messengers! How often I have wanted to gather your children together as a hen protects her chicks beneath her wings, but you wouldn’t let me. And now, look, your house is abandoned and desolate. For I tell you this, you will never see me again until you say, ‘Blessings on the one who comes in the name of the LORD !’”
The LORD is Yahweh......and in almost 2000 years, the Jews as a nation have never accepted, let alone blessed Jesus as the Christ....the one who came in the name of his God and Father, Yahweh....and they never will...pride won't let them.
So God changed the definition of what it meant to be "Jewish".
In Romans ch 2 Paul explains what the problem was with natural Israel....
He said...
"If, now, you are a Jew in name and rely on law and take pride in God, 18 and you know his will and approve of things that are excellent because you are instructed out of the Law, 19 and you are convinced that you are a guide of the blind, a light for those in darkness, 20 a corrector of the unreasonable ones, a teacher of young children, and having the framework of the knowledge and of the truth in the Law— 21 do you, however, the one teaching someone else, not teach yourself? You, the one preaching, “Do not steal,” do you steal? 22 You, the one saying, “Do not commit adultery,” do you commit adultery? You, the one abhorring idols, do you rob temples? 23 You who take pride in law, do you dishonor God by your transgressing of the Law? 24 For “the name of God is being blasphemed among the nations because of you,” just as it is written."
What was God to do with this people who were the offspring of Abraham, and with whom he had made a covenant, when they repeatedly rebelled against him and disregarded his laws?
Paul identified a new kind of "JEW"..... ones who were circumcised in heart rather than the flesh.....ones who obeyed God's laws rather than ones who bent them to suit themselves.
"For he is not a Jew who is one on the outside, nor is circumcision something on the outside, on the flesh. 29 But he is a Jew who is one on the inside, and his circumcision is that of the heart by spirit and not by a written code. That person’s praise comes from God, not from people."
'Spiritual Israel' was brought into being with the selection of the foundation members of God's elect...his faithful apostles.
Added to these were the ones anointed by God's spirit to become "kings and priests" with Christ in heaven.... Those are the "we" you spoke of.
I am not part of that anointed group, as my hope is entirely earthly. ...the situation Jesus spoke about in the Revelation 21:1-5.