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The Counting of the Omer is a commandment in Judaism of counting the days that pass between Pesach (Passover) and Shavuot (the Feast of Weeks). This mitzvah (commandment) derives from a commandment in the Torah to count 49 days beginning from the day on which the Omer, a sacrifice containing an omer-measure of barley, was offered in the Temple in Jerusalem, up …