New answers tagged midrash
The story is found in מדרש שוחר טוב to Tehillim (39:2). (Menachem's comment [now deleted]) This is probably the earliest source. It is also quoted in the אורחות צדיקים (in שער כ"ה, שער לשון הרע) [on that page, toward the bottom in blue text] (from Menachem, in another deleted comment) According to he.Wikipedia, this story is also quoted in אגדות המלך שלמה ...
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