All of it rightly belongs to Him as the Son of God. As such, He has all the rights to it. Add to the fact that it is only to such character as His that one can rightly and properly be the heir and ruler of the entire universe.
Now, God is a God of love. And love loves to share and dispense what it has. And so God in eternity past decreed that He would share and allow others to partake of the blessings He promised to His Son who will be united to Him in redemption and salvation.
The Lord Jesus Christ was ultimately the Chosen One to enjoy and inherit all these blessed promises, however, anyone who is united to Him through faith, through the enablement of His grace, are chosen in Him to enjoy the promised blessings.
Just as every single Israelite became part of the chosen nation Israel through their chosen father Abraham, through physical birth, to inherit the blessed promises God made to Abraham, so anyone now, in this dispensation, who is born again, one who is a new creature in Christ, becomes chosen in Christ to enjoy and partake of His promised glory.
The sphere and basis of election is the Lord Jesus Christ Himself:
Eph 1:4 even as He chose us IN HIM before the foundation of the world, that we should be holy and blameless before him.
Notice that it does not say: "even as He chose us TO BE IN HIM before the foundation of the world..." Rather, it says: "even as He chose us IN HIM..."
Christ is the sphere and the foundation of election. If you are IN Him, you are elect and chosen. I am not chosen and elected because of anything in me. No, I am chosen because of Him!
Election is a very Christ-centered doctrine in the Bible. Properly understood, it does not drive us to be occupied with ourselves and ask: "Am I elect or not? Am I elect or not?" Rather, it should make us ask: "Am I in Christ or not? Am I united to Him? If I am in Him, then I know I am elect."
Just as salvation is in Christ, so is election in Christ.
Ephesians 1 is an IN CHRIST chapter. At least eleven times, the idea of being in Him is repeated over and over again. This is the key to understanding the chapter. Miss this and you fail to get what Paul is trying to say.
All the spiritual blessings enumerated in the chapter is said to be IN CHRIST, including election.
Christ is the chosen ship that stores all of God's spiritual blessings. Anyone in Him will enjoy and possess all of these blessings. Predestination is one of the blessings inside the ship. Think of predestination as the blessed destination of the chosen ship.
If you notice, Paul never explained election in any of his letters. He just assumed that his readers already knew about it. This is because election in Paul's view is similar to that in the Old Testament. And the Old Testament was widely read during their times, even by the Gentiles.
We get our definition of election now from theologians like Calvin etc.
The Jews were very proud of their race. They could claim that they were God's chosen nation. They say that they were God's chosen because of physical descent from Abraham, because they had the Law of Moses etc.
They were chosen not TO BE in Israel. As if they were outside of Israel at first, but God chose them in. And so that's how they became eventually in. No, they were chosen because they were in Israel by birth. Anyone in Israel was chosen because of their relationship to Abraham.
In the same way now, a sinner is chosen in Christ by virtue of his new birth in Christ.
Many of them treated non-Jews (the Gentiles) as second class citizens in God's kingdom. They say that to a degree, Gentiles must become Jews to enjoy God's full blessings.
The apostle Paul had to fight tooth and nail to have this idea eradicated. In his letters, he would assure non-Jewish Christians that they themselves were chosen by God because they were in Christ. Christ is chosen (1 Peter 2:4), they are part of His body, therefore they were chosen too. No need to become a Jew. No need for Jewish rituals, regulations etc.
When Paul wrote in Romans 9:15 about God saying: "I will have mercy on whomever I will have mercy, and I will have compassion on whomever I will have compassion", he was not using it to LIMIT God's mercy.
He was referring to God's prerogative to have mercy on anyone, NOT JUST JEWS! The verse is quoted to show that God can have mercy on anyone. He made it very clear afterwards!
Ro 10:12 For there is no distinction between Jew and Greek, for the same Lord over all is rich to all who call upon Him.
Ro 11:32 For God has committed them all to disobedience, that He might have mercy on all (whether Jew or Gentile).
What if God will show mercy to believing Gentiles? Can anyone object to it? He is God. He has the prerogative to do it.
The Jews need to understand that God saves not by physical descent from Abraham. That they don't have the monopoly of God's mercy exclusively. God has chosen those who are in Christ, Jew or Gentile to enjoy His blessings.
Right now, in the meantime, God is molding and transforming those who are in Christ to be conformed to His image. It's training time for them for reigning time with Christ in the future.
Election in the New Testament is God in His foreknowledge choosing those in Christ to enjoy the blessings and privileges and promises He made to Christ.
