Ecc 10:10 If the iron is blunt, and one does not sharpen the edge,
he must use more strength,
but wisdom helps one to succeed.
Jer 31:29 In those days they shall no longer say:

“‘The fathers have eaten sour grapes,
and the children’s teeth are set on edge.’

Jer 31:30 But everyone shall die for his own iniquity. Each man who eats sour grapes, his teeth shall be set on edge.

Eze 18:2What do you mean by repeating this proverb concerning the land of Israel, ‘The fathers have eaten sour grapes, and the children’s teeth are set on edge’?
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