The relationship between God and the Israelites is vividly illustrated through the absolute authority a craftsman holds over his raw material. The primary approach among commentators is that God clarifies His ability to guide and mold the nation exactly as a potter works with his clay.
If a vessel becomes ruined or spoiled during the crafting process, the potter can simply take that very same material and reshape it into an entirely new vessel. In the exact same way, the ultimate fate of the nation rests entirely with God. The Israelites are completely subject to His decisions, molded and guided by His will, just as raw clay is shaped by whatever the potter desires to create.