1. Return, faithless Israel (3:6-18)
Israel committed spiritual adultery with idols. Unfaithful Judah had no fear and committed the same sin. Judah turned to God only in pretense. God gave Israel the chance to admit their guilt and return to him. God would even give them shepherds after his heart (15). Jerusalem would be the Lord's throne and all nations would honor the Lord.
2. Circumcise your hearts (3:19-4:4)
Israel perverted their ways and forgot God. If they returned, God would cure them of backsliding (22). If they confessed their sin and disobedience, the Lord would be their salvation (23,25). They simply needed to put their idols away and come to God in a truthful, just and righteous way (4:3). Judah also had to circumcise their hearts to avoid God's wrath.