Malbim: Also Yirmeyah's final words, which he said on his own, that they do not intend to heed the Navi's words, also this Hashem commanded him to tell them ¹ . Even though it depends on choice, and they can choose to heed Hashem's voice, Hashem informed him of their intent. They deceive the Navi and resolved not to listen if Hashem will say not to go to Egypt. They thought that Yirmeyah said so on his own. Therefore, they thought that the entire Nevu'ah he said on his own.