John Gill Commentary Jeremiah 38:21

"But if thou refuse to go forth, this is the word that Jehovah hath showed me:" — Jeremiah 38:21 (ASV)

But if you refuse to go forth Out of Jerusalem, to the Chaldean army, and submit to them: this [is] the word that the Lord has shown me, or the thing which should certainly come to pass; the word of prophecy the Lord had shown to the prophet, and which he now declares to the king; who asked of him a word, was desirous to know whether there was a word from the Lord, and what it was; and this it is which follows, in case he continued impenitent, obstinate, and disobedient.