John Calvin Commentary Jeremiah 39:8

"And the Chaldeans burned the king`s house, and the houses of the people, with fire, and brake down the walls of Jerusalem." — Jeremiah 39:8 (ASV)

Here also the Prophet shows that whatever he had predicted was fulfilled, so that nothing was lacking to make faith sure and fixed. He had said, as we have seen, that if Zedekiah surrendered himself of his own accord, the houses in the city would not be burned. Zedekiah thought this all vain, or at least he closed up his ears. He now heard, though he was blind, that God had declared nothing in vain by the mouth of Jeremiah, for his palace was burned, and also all the other houses.

He used בית , bith, in the second clause, the singular for the plural; and so there is an enallage here, for it was not only one house of the people that was burned, but the fire consumed all the houses. At last, we come to the walls, which were beaten down; and thus the city was destroyed as Jeremiah had predicted.