In a subtle discussion of divine repentance, R.W.L. Moberly (Old Testament Theology, 122-3) offers this complex reading of Jeremiah 18:1-10.
Rather than a contradiction, he suggests that it offers a “striking paradox.” The imagery “strongly emphasizes divine power,” yet at the same time “we have a strong statement of divine responsiveness to human attitude and action.” God is free, “in effect entirely unconstrained in terms of the potter imagery,” yet He “commits Himself to responsive action.” God doesn’t cease to be free, but His freedom is “moral and relational: it takes into account the responsiveness, or lack of it, that humans display. Divine power is exercised not arbitrarily, but responsibly and responsively, interacting with the moral, or immoral, actions of human beings.”
In fact, he suggests, this responsiveness is built into the potter-clay analogy: “people skilled in a craft are regularly highly sensitive and thus responsive to the nature and texture of the material with which they work.” Being clay doesn’t mean that we human beings are “helpless objects dependently solely on the decisions of the potter, but rather as able to make some difference to him.”
In sum, “to say that God repents implies that God’s relationship with humanity in general, and with Israel in particular, is a genuine and responsive relationship, in which what people do and how they relate to God matters to God” (129).
Moberly finds a similar complexity in Paul’s use of the potter-clay imagery. On the one hand, Paul uses “the image of the divine potter . . . solely to express divine power,” yet his strongly predestinarian claims in Romans 9 should be held together with his emphasis on God’s responsiveness to human repentance found in chapter 11 (141-2). As in Jeremiah 18, Paul speaks of God’s sovereignty and of God’s responsiveness; neither Jeremiah nor Paul “separate the two nor play them off against each other” (142).