Our fathers have sinned, and are not; and we have borne their iniquities. Our fathers ... sinned, and are not; and we have borne their iniquities - (Jeremiah 31:29, "The fathers have eaten a sour grape, and the children's teeth are set on edge").
Borne their iniquities - i:e., the punishment of them. The accumulated sins of our fathers from age to age, as well as our own, are visited on us. They say this as a plea why God should pity them, (cf. Ezekiel 18:2, etc.)