John Calvin Commentary Jeremiah 31:25

"For I have satiated the weary soul, and every sorrowful soul have I replenished." — Jeremiah 31:25 (ASV)

By this verse he removes every doubt, so that no one would reject what he had promised concerning the restoration of the people, because the Jews and the Israelites were at that time like dead men. He therefore says, I will water the thirsty soul; some render it “the weary soul,” but נפש עיפה, nupesh oiphe, is often taken metaphorically for a thirsty soul. So in Psalm 143:6, it is said:

I am as a dry land;

Weariness cannot be suitably applied to land; and in Isaiah 29:8, we have these words:

As one dreaming he thinks that he eats; afterwards, when awake, his soul is empty: and as one who thinks that he drinks,

etc. The Prophet uses the same word there, because there is hardly ever weariness without thirst; we contract thirst through weariness.

Thus, the soul is said to be עיפה, oiphe, by a metaphor—not weary, but on the contrary, thirsty. The corresponding verb means to inebriate, to irrigate, or to water, and often to satiate.

I will then irrigate, or water to satiety, your dry soul, and every soul which faints, etc. But as דאב, dab, means to be deficient, and sometimes to be wearied, here it denotes a defect, for it follows, I will fill. It is then to be understood as a famished soul.

The meaning is that even if the Israelites should hunger and thirst, and be for a time without food and drink, their need would still not prevent God from providing them relief. For He had the power and the will to satisfy the hungry and to give drink to the thirsty, or to those who were fainting because of thirst.