Megillah 11 - Computational mistake
The Megillah starts with a description of a great feast thrown by King Ahashverosh. What exactly was celebrated? - that God has abandoned the Jews and will no longer redeem them.
Ahashverosh sought to correct the previous mistake, and based on the analysis of the writing, he started counting seventy years from a different historical event. However, he celebrated in the same manner by using the Jerusalem Temple's vessels at the banquet. This started the chain of events that the Megillah describes, including the killing of Ahashverosh's wife, Vashti, who was the daughter of Belshazzar.
But Ahashveroshes's calculations seemed correct!? - He should have started from the year of the destruction of the Temple.
Art: Frans Francken Belshazzar Feast
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