Adam Clarke on Jeremiah 2:13

Two evils - First, they forsook God, the Fountain of life, light, prosperity, and happiness. Secondly, they hewed out broken cisterns; they joined themselves to idols, from whom they could receive neither temporal nor spiritual good! Their conduct was the excess of folly and blindness. What we call here broken cisterns, means more properly such vessels as were ill made, not staunch, ill put together, so that the water leaked through them.