Remember Israel- the Jews are Gods Elect/ Chosen people.
Pauls summary of Romans 9:
Faith vs Works is what Paul is addressing in Romans 9. Gentiles ( non elect by faith ) Jews/Israel ( Gods elect,chosen) by works.
Romans 9
That
the Gentiles, who did not pursue righteousness, have obtained it, a righteousness that is
by faith; 31 but the people of
Israel, who pursued the law as the way of righteousness, have not attained their goal. 32 Why not? Because they pursued it not by faith but as if it were
by works. They stumbled over the stumbling stone. 33 As it is written:
“See, I lay in Zion a stone that causes people to stumble
and a rock that makes them fall,
and the one who believes in him will never be put to shame.
The above is the same teaching in Romans 3 below :
Romans 3
But now the righteousness of God has been manifested apart from law, although the law and the prophets bear witness to it, 22 the righteousness of God through faith in Jesus Christ for all who believe. For there is no distinction; 23 since all have sinned and fall short of the glory of God, 24 they are justified by his grace as a gift, through the redemption which is in Christ Jesus, 25 whom God put forward as an expiation by his blood, to be received
by faith. This was to show God’s righteousness, because in his divine forbearance he had passed over former sins; 26 it was to prove at the present time that he himself is righteous and that he justifies him who has faith in Jesus. 27 Then what becomes of our boasting? It is excluded. On what principle? On the principle of works? No, but on
the principle of faith. 28 For we hold that a man is justified by faith apart from works of law. 29 Or is God the God of Jews only? Is he not the God of Gentiles also? Yes, of Gentiles also, 30 since God is one; and he will justify the circumcised on the ground of their faith and the uncircumcised
through their faith.
And if we keep reading into chapter 9 the hardened Jew/reprobate is whom Paul prays for in their temporary hardening until all the gentiles are grafted into the branch. The potter/clay is God using the hardened Jews- His elect,chosen people ( destruction ) to bring in non elect vessels of glory ( gentiles) their salvation. The potter/clay is another analogy that contradicts calvinism, not support it. Once the glasses/lens are removed one can see the passages in their greater biblical context and harmonize them.
hope this helps !!!