The Potter and the Clay
"Nay but, O man, who art thou that repliest against God? Shall the thing formed say to him that formed it, Why hast thou made me thus? Hath not the potter power over the clay, of the same lump to make one vessel unto honour, and another unto dishonour? What if God, willing to shew his wrath, and to make his power known, endured with much longsuffering the vessels of wrath fitted to destruction: And that he might make known the riches of his glory on the vessels of mercy, which he had afore prepared unto glory," Romans 9:20-23
The figure of the Potter and the clay is not introduced for the first time in Romans 9. The writer is citing scriptures in the Old Testament that make the same point that he is making here in Romans. Consider the following...
"O house of Israel, cannot I do with you as this potter? saith the LORD. Behold, as the clay is in the potter's hand, so are ye in mine hand, O house of Israel. At what instant I shall speak concerning a nation, and concerning a kingdom, to pluck up, and to pull down, and to destroy it; If that nation, against whom I have pronounced, turn from their evil, I will repent of the evil that I thought to do unto them. And at what instant I shall speak concerning a nation, and concerning a kingdom, to build and to plant it; If it do evil in my sight, that it obey not my voice, then I will repent of the good, wherewith I said I would benefit them." Jeremiah 18:6-10
We see here that the Potter is the Lord, and the clay is the nation of Israel. The context of this analogy is not individual souls believing or not believing. The context is how God deals with the Jewish people depending on their response to Him, building them up, or tearing them down.