John Calvin Commentary Jeremiah 38:6

"Then took they Jeremiah, and cast him into the dungeon of Malchijah the king`s son, that was in the court of the guard: and they let down Jeremiah with cords. And in the dungeon there was no water, but mire; and Jeremiah sank in the mire." — Jeremiah 38:6 (ASV)

Here, the extreme presumption as well as cruelty of the princes is narrated; for they cast the holy Prophet into a pit, where he sank in the mire. It was a proof of hardened impiety not to spare so excellent a servant of God; and it was also savage cruelty, when they had no cause for such rage, except that Jeremiah had obeyed God and faithfully performed the duty entrusted to him.

Let us also learn from this example, whenever the Lord chooses to test our patience, to bear with resignation what we see the holy Prophet endured. If, then, we ever shudder at the horrors of the cross, so that bearing persecution may seem hard to us, let us remember this example of the Prophet. In a word, here, on the one hand, the wickedness of the world is shown to us, as in a picture; and on the other, the wonderful steadfastness and also the singular meekness of God’s servant shine forth gloriously.

Jeremiah then says that he was taken by the princes and cast into a pit, which was in the court of the prison; and in that part where one of the counselors lived, even Malchiah the son of Hamelech. He also describes the state of the place: that it was a miry pit, so that he sank down in the mud. He does not mean that he was covered with mud, but that he was fixed in it, as the Hebrew word indicates; and we may thus rightly translate the words, “He lay fixed in the mud.”