Be appalled, O heavens, at this; be shocked, be utterly desolate, declares the LORD, for my people have committed two evils: they have forsaken me, the fountain of living waters, and hewed out cisterns for themselves, broken cisterns that can hold no water.
God's message through the prophet is that Israel has sinned deliberately against God in two ways. The first is the sin of rejection. God had provided sustaining relationship: fountains of living water. This was a vivid and lively metaphor for those who lived in a semi-arid Mediterranean climate of Israel. But they had rejected a sustaining obedience to The Lord.
Instead, a second sin marked their culture. They committed the sin of replacement: idolatry. They were left with broken cisterns they had hewn for themselves out of dry rock. Cisterns do not hold fountains of running water. They hold rain water that sits and stagnates over time. Again the metaphor is dramatic. Israel rejected the vibrant love of God and replaced it with a nasty malignancy that failed to sustain them. Idolatry never satisfies the heart.
All of Jeremiah 2 is a description of the apostate wanderings of an idolatrous people. It shows us what happens to a society that rejects God and attempts replacement. In the end its own desperation takes over as the leading edge of God's judgment against these two sins. These warnings are instructive because humans have not changed. If I do not trust God, I will make an object of faith for myself and it will fail me. That is the tragedy of worshiping anything other than God alone.