Jeremiah 3:3

Therefore the showers have been withholden, and there hath been no latter rain,.... There were two seasons of the year when rain in common fell upon the land of Israel, called the former and the latter rain, and both are designed here. The former by רביבים, "showers", so called from the multitude of drops in them: these showers, or the former rain, used to fall in the month Marchesvan, which answers to part of our October; it was in autumn, at the fall of the year, at seedtime, when great quantity of rain usually fell, to prepare the earth for sowing, and watering the seed sown; whence that month was sometimes called Bul, as Kimchi observes, from "mabbul", a flood. The latter rain fell in Nisan, which answers to our March; it was in the spring, a little before harvest, which swelled the grain, made the skin the thinner, and the flower the finer. This is called מלקוש: now, because of the idolatry of these people, those rains were withheld from them, as they were in the times of Ahab, 1 Kings 17:1, which brought a famine upon them; and was a manifest token of the divine displeasure, and what was threatened them in case they sinned against the Lord,

Deuteronomy 28:23:

and thou hadst a whore's forehead; was impudent and unconcerned, repented not of sin, or blushed for it, though such judgments were upon them; hence the Rabbins x say rains are not withheld but for impudence, according, to this Scripture:

thou refusedst to be ashamed; to be made ashamed by the admonitions of the prophets, or by the judgments of God; see Jeremiah 5:3.

x T. Bab. Taanith, fol. 7. 2.