Romans 9 - maybe one of the most revealing, challenging and mysterious chapters in the bible. Paul had "great sorrow and unceasing anguish in his heart", because his Jewish kinsmen are only kinsmen according to the flesh - "for not all who are descended from Israel belong to Israel, and not all are children of Abraham because they are his offspring."
Paul is quick to cover the natural human objection to his writing: Romans 9:14 What shall we say then? Is there injustice on God's part? By no means! 15 For he says to Moses, “I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion.” 16 So then it depends not on human will or exertion, but on God, who has mercy.
Paul further anticipates the follow-up objection. Well, if it depends not on how I behave, but on God who has mercy, how can He find fault in me?
Romans 9:19 You will say to me then, “Why does he still find fault? For who can resist his will?” 20 But who are you, O man, to answer back to God? Will what is molded say to its molder, “Why have you made me like this?” 21 Has the potter no right over the clay, to make out of the same lump one vessel for honorable use and another for dishonorable use? 22 What if God, desiring to show his wrath and to make known his power, has endured with much patience vessels of wrath prepared for destruction, 23 in order to make known the riches of his glory for vessels of mercy, which he has prepared beforehand for glory— 24 even us whom he has called, not from the Jews only but also from the Gentiles? 25 As indeed he says in Hosea,
“Those who were not my people I will call ‘my people,’
and her who was not beloved I will call ‘beloved.’”
26 “And in the very place where it was said to them, ‘You are not my people,’
there they will be called ‘sons of the living God.’”
27 And Isaiah cries out concerning Israel: “Though the number of the sons of Israel will be as the sand of the sea, only a remnant of them will be saved, 28 for the Lord will carry out his sentence upon the earth fully and without delay.” 29 And as Isaiah predicted,
“If the Lord of hosts had not left us offspring,
we would have been like Sodom
and become like Gomorrah.”
30 What shall we say, then? That Gentiles who did not pursue righteousness have attained it, that is, a righteousness that is by faith; 31 but that Israel who pursued a law that would lead to righteousness did not succeed in reaching that law. 32 Why? Because they did not pursue it by faith, but as if it were based on works. They have stumbled over the stumbling stone, 33 as it is written,
“Behold, I am laying in Zion a stone of stumbling, and a rock of offense;
and whoever believes in him will not be put to shame.”
Note to self: Be careful not to create a God that only makes sense (fits comfortably) to me in my limited human mind. Whether I believe something about God is true or not has absolutely zilch to do with whether it is actually true of Him. He is who He is.
