During a famine, Joseph's brothers came to Egypt for relief.
Joseph received them, his face covered with a veil.
As they spoke, Joseph kept striking a cup which resounded mournfully.
Finally, Joseph's brothers could bear it no longer. "What is the meaning of this mournful sound?" they asked.
Joseph struck the cup. "The cup says you had a brother named Joseph."
Again. "It says you threw Joseph into a well."
Again. "You sold him into slavery."
Again. "You told your father his son was dead."
Joseph's brothers all wept and were afraid.
Now they were the ones in the well.
Inspired by: The Conference of the Birds by Farid Ud-Din Attar, translated by S. C. Nott
Notes: This is in section 31: Joseph and his Brethren.