Parashat Ki-Tisa begins with the mitzva of machatzit ha-shekel – the annual half-shekel tax paid by every member of the nation which was used to fund the public sacrifices in the Beit Ha-mikdash.
The Midrash (Tanchuma, Ki-Tisa 5) draws an association between this mitzva and the sin of the golden calf, of which we read later in the parasha. The Torah commands with regard to the machatzit ha-shekel, “Zeh yitenu…machatzit ha-shekel” – “This is what they shall give…a half –shekel…” The word “zeh” (“this”), the Midrash observes, also appears in the context of the golden calf, as when the people approached Aharon and asked that he make an idol for them, they said, “Ki zeh Moshe ha-ish…lo yadanu meh haya lo” – “For this man, Moshe - we do not know what happened to him.” The Midrash comments, “[The nation] was lowered with the term ‘zeh’ and was elevated with the term ‘zeh’.” Somehow, the mitzva of the half-shekel serves as the antidote, or rectification, of the golden calf, “elevating” the nation after it had plummeted to the depths of idol-worship.
The basis for this link can perhaps be found in the particular verse cited by the Midrash, in which Benei Yisrael explain to Aharon their need for a new leader: “For this man, Moshe - we do not know what happened to him.” One of the causes of cheit ha-eigel (the sin of the calf) was the people’s overdependence on Moshe. As soon as they concluded that Moshe would not be returning from the top of Mount Sinai, they concluded that they must abandon everything he taught them. Without Moshe, the people figured, they cannot follow the faith they learned from him. They therefore did a complete about-face, returning to the idolatrous beliefs and practices of Egypt, convinced that they had no other choice now that Moshe was gone.
The rectification of this mistaken outlook is the machatzit ha-shekel, a mitzva which underscores the powerful effect of each individual’s own small contribution. God’s presence is brought into and kept in the Mikdash not through “Moshe Rabbenu,” the nation’s leader, but rather through the humble donation made by each and every member of the nation. This mitzva emphasizes that what matters most is not the person at the top, but rather each person making his or her own contribution. Cheit ha-eigel occurred because the people felt they could not continue without Moshe; the machatzit ha-shekel conveys the message that we can, as long as each person does his or her share and we work together to bring the Divine Presence into our midst.