Jesus told the Jews, “Your father Abraham rejoiced to see MY DAY: and he saw it, and was glad” (John 8:56).
These Jews were standing in the presence of the Son of God, the Messiah, the Shepherd and King of Israel, yet they accused Him of falsehood and ridiculed Him.
Do you think God had a plan for “these Jews” apart from Christ? Do you think God required the Romans to bless THESE Jews in order to be blessed?
When God said, “I will bless those who bless you and curse those who curse you,” He was talking TO Abraham, and not to Israel.
These Jews missed the blessing of Abraham, and unless they repented somewhere between this dialogue in John 8, and the time of their death, they were cursed and have been separated from God for nearly 2000 years.
The apostle Peter preached to the Jews telling them, “UNTO YOU FIRST God, having raised up his Son Jesus, SENT HIM TO BLESS YOU, in turning away every one of you FROM HIS INIQUITIES.
Paul told the Galatians that Jesus bore the curse of the Law so that “THE BLESSING OF ABRAHAM” might come upon the Gentiles.
The blessing which God promised Abraham, saying, “I will bless those who bless you,” is in reference to Abraham becoming the father of many nations. This blessing comes ONLY through Jesus Christ. This blessing is not on national modern Israel, this blessing is in Christ, and it is upon those who are in Christ.
God told Abraham. “I will bless them that bless THEE , and curse him that curseth THEE: and IN THEE SHALL ALL FAMILIES OF THE EARTH BE BLESSED” (Genesis 12:3).
In Galatians, the apostle Paul refers to this as the gospel in advance.
And the scripture, foreseeing that God would justify the heathen through faith, preached before THE GOSPEL unto Abraham, saying, IN THEE SHALL ALL NATIONS BE BLESSED. So then they which be of faith are BLESSED WITH FAITHFUL ABRAHAM (Galatians 3:8-9).