John Calvin Commentary Jeremiah 14:4

"Because of the ground which is cracked, for that no rain hath been in the land, the plowmen are put to shame, they cover their heads." — Jeremiah 14:4 (ASV)

The Prophet had said that even if all the common people were to go to the waters, yet none would be found. He now adds the same warning concerning the farmers. Ashamed, he says, shall be the husbandmen, for the ground shall be turned into dust, and God will pound it small. When the heavens supply moisture, the earth thus retains its solid character; but in great heat, we see the earth dissolving into dust, as if it were pounded in a mortar.

So he says, On account of the chapt ground, because there is no rain, ashamed shall be the husbandmen, and they shall cover their heads; for sorrow will not only seize them, but also fill them with such shame as to make them shun the light and the sight of men. These things were intended for the same purpose: to make the Jews know that they were not by chance deprived of water, but because God had cursed their land, so that it yielded them no water, even for the common needs of nature.