Commentators disagree over the circumstances which mandate the donations detailed in Shemot 30:12-16. One group of commentators explain that the census is the critical factor. Within this option, Shadal maintains that half-shekels were given only in the very first census in the wilderness, while Rashi asserts that a similar procedure was followed in subsequent countings as well. A second category of exegetes argues that support of the Mishkan or Mikdash is the main purpose, and that there is no need to give during a census. This view also divides, with Rashbam positing that the verses describe a one-off campaign to build the Mishkan, and R. Saadia claiming that the Torah is speaking of an annual obligation to support the Mishkan/Mikdash. Finally, exegetes like the Minchah Belulah and the Vilna Gaon suggest that there are multiple factors at work, and each of a census and the maintenance needs of the Mishkan/Mikdash require their own collection.
Census Focused
Shemot 30:12-16 commands Moshe to conduct a census using shekalim, rather than through a simple headcount. While the proceeds are used for the Tabernacle, this is not the main objective, and the Torah is not mandating a regular donation to the Mikdash.
One-time Obligation
These verses were an instruction for this single occasion only to count the nation via the giving of half-shekels. All future censuses, in contrast, do not require a similar donation.
"כִּי תִשָּׂא" – Shadal asserts that this was a one-time command2 to count the nation via half-shekels.3 The census is being taken at this point, as the people have just become a nation.
Concern of a plague – Shadal asserts that a census can often lead to feelings of self-confidence and hubris ("כֹּחִי וְעֹצֶם יָדִי") which, in turn, brings about punishment and devastation. The people viewed these consequences as being the result of the "evil eye," an erroneous notion that God did not correct.4 As such, Hashem told them to bring a half-shekel which could act as an atonement and save them from any negative repercussions of the counting.56
Why only one time? The donations were used to build the Tabernacle which was then able to provide protection against any negative consequences from future censuses.7
"עֲבֹדַת אֹהֶל מוֹעֵד" – The monies collected were used for the original construction of the Tabernacle. The requirement was not motivated by a need for donations,8 and was not mandated for any future upkeep. "עֲבֹדַת אֹהֶל מוֹעֵד", thus, refers not to maintenance and continued service in the Tabernacle, but to the initial building.
Censuses in Bemidbar 1 and 26 – In both of these censuses, the nation was not counted via half-shekels, and thus none are mentioned.
Shaul's censuses – These do not mention a half-shekel, as none were needed.
David's census and Divine punishment – David was punished not because he did not count via shekalim but because he counted without good reason, just for his own glorification.9
Contributions mandated by Yoash – Shadal might propose that this was a special command of Yoash to bring donations for renovations of the Temple. Yoash is upset not because the people are not fulfilling a Torah prescription, but because of the lack of contributions. It is possible that he refers to these monies as "מַשְׂאַת מֹשֶׁה" not because they were originally mandated by Moshe, but to give more credence to his request, and to compare them to the nation's original donations to the Tabernacle.
One-third shekel donation in Nechemyah – This donation has nothing to do with a census but was rather a decision by the nation to contribute yearly to the Temple.
The custom of giving half-shekels –
All Future Censuses
These verses constitute an enduring ordinance that all future censuses be performed, not via a forbidden headcount, but rather through the counting of donated items such as half-shekels.
"כִּי תִשָּׂא" – Rashi reads this phrase as a command to immediately count the people. According to Rashi, these verses are out of chronological order and were told to Moshe only after the sin of the Golden Calf.11 He explains that since many people had just died as a punishment for their idolatry, a census was required. Rashi further states that the total from this census is transmitted in Shemot 38:26.12
Concern of a plague – Rashi explains that a simple headcount without using shekalim might bring on an "עין הרע" ("evil eye"), and this could result in a plague.
Censuses in Bemidbar 1 and 26 – Rashi states that the census in the second year in the wilderness was also performed using shekalim.13
Shaul's censuses – According to Rashi, both of Shaul's counts utilized objects, rather than simply counting the people themselves. He reads "בְּבָזֶק" and "בַּטְּלָאִים", as the names of those objects.
David's census and Divine punishment – Rashi understands that a plague came in the time of David because he counted the people without using shekalim.
"עֲבֹדַת אֹהֶל מוֹעֵד" – The silver collected from the census in the first year was used for the silver sockets of the Tabernacle. Thus, for Rashi, "עֲבֹדַת" refers to the construction work of the Mishkan, rather than its ongoing service.
Contributions mandated by Yoash –
One-third shekel donation in Nechemyah –
The custom of giving half-shekels –
Mishkan Contributions
The Torah is mandating financial support for the Mikdash, and a census is merely a vehicle through which this is achieved.
One-time Building Fund
These verses were a transient command to donate for the construction of the Tabernacle, which applied only to the nation in the first year of the wilderness. This obligation does not apply to future generations.
Why only one time? Most of these commentators maintain that the collection was required for the initial construction of the Tabernacle, and as such was a one time donation. According to Qumran 4Q159, in contrast, every individual is simply required to give a once in a lifetime contribution.14
"כִּי תִשָּׂא"
Rashbam appears to view the census as a by product of the collection; once Moshe was gathering the people to collect donations, he also counted them.15
Hoil Moshe, who posits that the verses are achronological and occurred after the sin of the Golden Calf, proposes that Moshe desired to count the remaining members of the nation. Hashem saw this as an opportunity to collect money which could serve as an atonement for their sin and be used to build the Tabernacle.16
Concern of a plague – Hoil Moshe views the shekalim as atonement for the sin of the Golden Calf, and might suggest that without them, the nation would have deserved further punishment. The others do not address the issue.
"עֲבֹדַת אֹהֶל מוֹעֵד" – According to most of the commentators, this refers to the initial building of the Tabernacle. According to Qumran 4Q159, in contrast, it refers to ongoing service.
Censuses in Bemidbar 1 and 26 – No shekel donations are mentioned since regular censuses do not require such a contribution.
Shaul's censuses – Shaul did not count via shekalim since there is no obligation to do so.
David's census and Divine punishment – Hoil Moshe asserts that David is punished for the actual counting, not for the fact that he did so without taking some redemption from the people.17 As David's decision to count stemmed from a desire for honor and had no other utility, it deserved punishment.18
Contributions mandated by Yoash – This approach could suggest that Yoash, on his own, requested contributions for the upkeep of the Mikdash, unconnected to any Torah obligation.19
One-third shekel donation in Nechemyah – This can be viewed as a new obligation taken by the people upon themselves after returning to Israel. Presumably, they were influenced by the original donations given in Shemot.20
The custom of giving half-shekels – This approach would assert that this is simply a custom, likely learned from the original contributions for the Tabernacle.
Ongoing Maintenance
These verses are an eternal mitzvah to provide annual support for the Mishkan or Mikdash.
Concern of a plague – The plague results from a laxity in giving contributions to the Tabernacle or Temple and is unrelated to the census.21
"עֲבֹדַת אֹהֶל מוֹעֵד" – This refers to the general upkeep and ongoing service of the Temple, including provisions for the sacrifices and the like.22
Census in Pekudei –
Censuses in Bemidbar 1 and 26 – As there is no obligation to count via shekalim, none are mentioned in these censuses.
Shaul's censuses – Here, too, there is no mention of shekalim since they are not a requirement for counting.
David's census and Divine punishment – R. Saadia asserts that David erroneously believed that the plague resulted from his counting, when in reality it was due to a different sin altogether, the nation's participation in Avshalom's rebellion.
Contributions mandated by Yoash – This story serves as the basis for this position. R. Saadia Gaon and Ibn Ezra prove from Yoash's rebuke to the nation "מַדּוּעַ לֹא דָרַשְׁתָּ עַל הַלְוִיִּם לְהָבִיא מִיהוּדָה וּמִירוּשָׁלִַם אֶת מַשְׂאַת מֹשֶׁה" that the annual contributions are mandated by Moshe in the Torah.
One-third shekel donation in Nechemyah – According to R. Saadia this was an additional third beyond the half shekel mandated by the Torah. As the returning nation was small in number, they realized that the temple expenses would not be covered if each just gave a half shekel.23
The custom of giving half-shekels – According to R. Saadia, this is not just a custom, but a Torah-mandated law.
Polemical motivations – R. Saadia may be motivated by a desire to find explicit support in Torah for the Rabbinic position regarding annual contributions to the Temple, in face of Karaites who claimed that there was no such obligation.
