במדבר, פרק ג׳, פסוק נ׳

The transition of sacred duties from the firstborn Israelites to the Levites required a precise exchange, person for person. However, a numerical imbalance remained, leaving exactly two hundred and seventy-three firstborns without a corresponding Levite to redeem them. To resolve this gap, a redemption price of five shekels was required for each of the extra individuals, resulting in a total collection of one thousand, three hundred and sixty-five shekels [ביאור שטיינזלץ]. This specific fund was drawn exclusively from the remaining unredeemed firstborns [חזקוני]. The explicit mention of the Israelites in this context serves to permanently exempt the firstborns of the Levites from any future obligation of redemption. Moses acted as the agent for this process, dealing directly with the adult firstborns who were obligated to pay, rather than collecting the funds through their fathers. Furthermore, the requirement to pay in the sacred shekel meant that actual silver coins had to be used, rather than items of equivalent monetary value [מלבי״ם]. Gathering the entire sum into Moses' hands was a unique, temporary instruction for this specific event; in standard redemption practices, the money is given directly to individual priests for their personal use [העמק דבר].

How this money was collected from a massive population of twenty-two thousand firstborns presents an interesting logistical challenge. One approach suggests that the financial burden was not placed on a specific group of two hundred and seventy-three men. Instead, the cost was distributed collectively among all the firstborns, with each individual paying a tiny fraction of the five-shekel price to cover the overall national gap [שד״ל].

However, the primary approach among commentators is that the payment was required from specific individuals. This presented Moses with a monumental leadership challenge. To prevent anyone from claiming they were already redeemed by a Levite and to avoid disputes, Moses organized a massive lottery [רש״י, ברכת אשר על התורה, שפתי חכמים]. He prepared small slips of paper, writing "Levite" to indicate an exemption, and "five shekels" to indicate an obligation to pay.

The exact execution of this lottery sparked further discussion, as a simple matching of slips to the population could lead to unrest. If Moses only prepared twenty-two thousand exempt slips, those at the end of the line might realize only obligated slips remained, sparking resentment and fights over who would draw first. To solve this, some suggest Moses conducted a preliminary lottery, similar to the finger-counting method later used in the Temple, to establish a fair order for drawing the slips without causing jealousy [לבוש האורה]. Other commentators offer a different solution: Moses prepared exempt slips equal to the entire population of firstborns—twenty-two thousand, two hundred and seventy-three—and mixed them with the two hundred and seventy-three obligated slips. By doing so, every person who approached the urn, from the first to the last, faced the exact same statistical probability of drawing an exemption. This constant, equal chance ensured the results were viewed as entirely fair and accepted by the people without complaint [שפתי חכמים, דברי דוד, ריב״א].