4:3,4 An unhumbled heart is like ground untilled. It is ground which may be improved; it is our ground let out to us; but it is fallow; it is over-grown with thorns and weeds, the natural product of the corrupt heart. Let us entreat the Lord to create in us a clean heart, and to renew a right spirit within us; for except a man be born again, he cannot enter into the kingdom of heaven.
3. Transition to Judah. Supply mentally. All which (the foregoing declaration as to Israel) applies to Judah.
and Jerusalem—that is, and especially the men of Jerusalem, as being the most prominent in Judea.
Break … fallow ground—that is, Repent of your idolatry, and so be prepared to serve the Lord in truth (Ho 10:12; Mt 13:7). The unhumbled heart is like ground which may be improved, being let out to us for that purpose, but which is as yet fallow, overgrown with weeds, its natural product.