The Shekolim Collection
Shabbat Shekalim, is the first of four special Sabbaths on which we read an additional Torah reading.
Shabbat Shekalim always falls at the advent of the month of Adar, but never after Adar has already begun.
When the Sanctuary, and later the Holy Temple stood, it was a mitzva for every Jew, rich or poor, to contribute half a shekel yearly for the purchase of the communal offerings brought in the Sanctuary.
All of the shekalim were due by the first day of the month of Nissan each year. On the first of the month of Adar public announcements were therefore made for the bringing in of the shekalim, so that each person would have sufficient time to prepare the half-shekel and to give it in the proper time.
Thus, our Sages enacted that on the Shabbat immediately preceding Adar or on the Shabbat on which the first day of Adar fell, the passage about the shekalim call was to be read from the Torah in the synagogue.
Until the Holy Temple is rebuilt, we cannot bring offerings and the mitzva of the half shekel does not apply. However, we read this portion at this time so that our reading of it might be considered like the fulfillment of the mitzva. In addition, the reading of this portion is in anticipation of the rebuilding of the Holy Temple at which time it will be necessary to be familiar with all of these mitzvot so that we will be able to perform them.
In our times, it is customary to give a half coin (for instance, in the United States a half-dollar) to charity on the eve of Purim as a remembrance of this special mitzva.
There are many beautiful explanations as to the significance of this mitzva in general as well as the reason for half a coin in particular. The Rebbe explains that this mitzva is performed with a half coin to remind us that each one of us is but "half a person" until we join together with another Jew in true love and unity. A half-shekel is given by all alike, no more and no less. In this mitzva we are totally united, those who are rich or poor in material matters and those who are rich or poor in spiritual concerns are united through the half- shekel.