πολλῶν ὑπῆρξεν Οἰδίπου κακῶν δόμοις τοδ'ἦμαρ

From LSJ

σταγόνες ὕδατος πέτρας κοιλαίνουσιν → constant dropping wears away a stone, constant dripping will wear away the hardest stone, little strokes fell big oaks, constant dripping wears the stone, constant dropping wears the stone, constant dripping will wear away a stone

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