If being a Zionist is to believe the state of Israel has a right to exist, like any of the other states of the United Nations, then I'm a Zionist. If it means to believe the Creator has a special calling for the Jews of today and throughout the ages, then I'm still a Zionist. If, to be a Zionist, I have to believe Jews can be saved through Judaism, then count me out.
The Abrahamic covenant included land for his descendants (Genesis 12:7; 13:15; 15:18), but Abraham had many descendants. Hagar and Ketura bore children for him as well as Sarah. They were originators of several nations (Genesis 17:4; 17:16), but according to Genesis 12:2 Abraham would be made into a great nation, singular. There is no reason why these other nations may not claim to be blessed because of their ancestor Abraham. But regarding the land, God made covenants with Abraham, Isaac and Jacob (Genesis 17:19; 24:7; 26:3; 28:13). His covenant with Israel is confirmed as eternal by the words of the prophets such as in Jeremiah 31:37. Paul told the Athenians that God fixed times and places for all nations (Acts 17:26).
God's covenant with Abraham was not only about land. Through his seed all the nations of the earth would be blessed. Paul interpreted this seed to be Jesus the Messiah (Galatians 3:16). This interpretation can also be derived from the gospels and Acts. Matthew 12:21 is a quotation from Isaiah 42:4 where it was prophesied that the nations would put their hope in his name. In Mark 11:17 Jesus applied Isaiah 56:7 to the temple, saying it was supposed to be for all nations. Paul quoted Isaiah 49:6 in Acts 13:47 to prove that Jesus would be a light to the nations.
None of these verses exclude the possibility that the Jews would also be a light to the nations. But Pharisaic Judaism cannot possibly make converts for the Kingdom of heaven. Jesus made that very clear by cursing the fig tree (Matthew 21:19), and also by means of the parable of the tenants of the vineyard (Matthew 21:33-45). The Pharisees knew he was implying that the keys to the Kingdom would be taken from them and given to another. The keys were given to the new custodians of salvation, namely the Church of the Messiah, Jews and gentiles (Matthew 16:18-19; Ephesians 3:6).
From time immemorial nations have had official religions. Since the time of Constantine there has been animosity between Jews and the official church of the Roman Empire and churches of the states originating from the empire. On both sides of the conflict there are those who incorrectly believe the Church belongs to the gentiles. From this perception many theologians draw the conclusion that the Church has replaced Israel.
State churches are based on the erroneous notion that all its citizens are people of God. If this assumption is accepted as true, then it follows logically that all the citizens of ancient Judah and Israel were people of God. That would mean the Church replaced ancient Israel and the covenant God made with Jacob regarding his descendants is no longer valid.
A more accurate understanding of modern Israel and of the Church is possible. The same people who persecuted the Jews over the last two millennia, also persecuted true believers in Jesus, especially those who rejected the baptism of infants as unscriptural. The reformers of Luther's day struggled with the question of who the members of the "true Church" were. Unfortunately they did not always have the courage of their convictions. This is very understandable if one considers the fate of John Huss, William Tyndale and thousands of "anabaptists".
Christians who support the BDS movement are misguided, engaging in "level 1 thinking", a term used by Daniel Kahneman in his book Thinking, Fast and Slow. They should examine their moral compass by thinking slower before drawing flawed conclusions about the Middle East conflict. They should consider the regimes with whom they align themselves. Freedom of religion is regarded by the United Nations as a fundamental human right but this right is denied by many of its member countries. Persons who support terrorist organisations must appease their consciences by believing "the end justifies the means".
There are also Christians who support Israel but pay scant attention to Paul's words regarding the gospel, namely "to the Jew first". Some of their support can even end up in the hands of Jews who persecute believers in Jesus, following in the footsteps of their forefathers who persecuted the prophets. Rather, Christians should be champions of Messianic Judaism in which Jewish believers observe Jewish culture.