Jeremiah 4:3 - Matthew Poole's English Annotations on the Holy Bible

To the men, Heb. man, i.e. to each man; I speak to every individual among you, Ezekiel 20:7,8. Of Judah and Jerusalem: the Lord having spoke what he had to say at present to Israel, turns now his speech from Israel to Judah, and so continues it; which consists of several subjects, and first begins with repentance. Break up your fallow ground, i.e. prepare your hearts by making them soft, tender, and pliable, fit to embrace my word; a metaphor taken from ploughmen, that do either prepare the ground that hath lain some time waste and untilled, by tearing up the surface of the earth, making it mellow and soft to receive the seed; (for the Hebrew word nir seems to be of larger extent than bare preparation; God useth the same word when he speaks to the same purpose to Israel, Hosea 10:13; and so it is used Proverbs 13:23) or it may relate to both, that every thing that may be injurious to the seed may be stubbed up. Or rather, From such as plough the ground. Sow not among thorns; rid you hearts and hands of what may hinder you of embracing my word; grub up all those briers, and thorns, and mischievous weeds that will not suffer my counsels to take, or my graces to thrive, with you; such as use to overrun the sluggard's field, Proverbs 24:30,31. Here the Lord begins to call upon them to repent. The phrase seems to intimate that the Jews had been wont to mix the truths of God among their own inventions, as seed among thorns, and so corrupted it; as also, that they retained many secret and hidden sins, like hypocrites, which he exhorts them to eradicate.