On the second day of Passover in ancient times, our ancestors brought the first sheaf of barley (amounting to a measure called "an omer") reaped that season as an offering to God. From that day, they began counting the 49 days to Shavuot, when they would celebrate the beginning of the wheat harvest by offering the loaves made of the first wheat. Even after the Temple was destroyed and offerings were no longer brought, they continued to count the days from Passover to Shavuot in accordance with the biblical injunction (Lev. 23:15).
 

In this way our ancestors linked Passover and Shavuot as occasions for thanking God for the fruits of the field. We, too, thank God for the renewal of life which nature proclaims at this season.
 

However, as Passover and Shavuot acquired historical significance, their linkage through the counting of the intervening days took on new meaning. Passover celebrates the liberation from Egypt, and Shavuot celebrates the receiving of Torah at Sinai. By counting the omer, we symbolically connect liberation with the idea of Torah.
 

Counting the omer is an exercise in the discipline of mindfulness. Counting each of the days of the omer reminds us that all of our days are numbered, and it is our responsibility to make each day count.