And the vessel he was making of clay was spoiled in the potter’s hand, and he reworked it into another vessel, as it seemed good to the potter to do.
He then relates what had been enjoined him, that he descended into the potter’s house; and then he relates what he saw there — that when the potter formed a vessel it was marred, and that he then made another vessel from the same clay, and, as it seems, one of a different form; for there is a peculiar emphasis in these words, as it seemed right in his eyes.
The prophet is here sent to the potter's house (he knew where to find it), not to preach a sermon as before to the gates of Jerusalem, but to prepare a sermon, or rather to receive it ready prepared. Those needed not to study their sermons that had them, as he had this, by immediate inspiration.
Commenting on Jeremiah 18:1-10
Then the word of the Lord came unto me, saying. While he was in the potter's house, and after he had observed his manner of working, and the change he had made in his work, the Lord spoke to him, and applied it in the following manner. Then the word of the Lord came unto me, saying.