Bechoros 46 - 52
No Exemption from Redemption
A Jew who is neither a Kohen nor a Levite, nor is his wife descended from such a family, is obligated to redeem his bechor (male first born) by giving five shekalim to a kohen. If the father failed to fulfill this obligation then the son must redeem himself in this manner.
What happens if a Jew who is about to redeem his bechor discovers that he is himself an unredeemed bechor but has only enough money to cover one redemption? There is a dispute in the Mishnah regarding priority and the halacha is that he must redeem himself rather than his son.
An interesting question arises in regard to this halacha. A Jew is not required to impoverish himself in order to fulfill a mitzvah and is even urged not to spend more than a fifth of his resources for such a purpose. How then can one be required to spend his entire "fortune" of five shekalim in order to fulfill the mitzvah of redeeming himself?
One resolution is offered by the Chafetz Chaim (Mishnah Berurah 656:1, Biur Halacha) who points out that the limitation of a fifth applies only to someone whose livelihood depends entirely on his resources and a severe reduction in the size of his resources will seriously threaten his economic stability. One who possesses only five shekalim, however, is obviously living on wages received for labor or services and his economic situation will hardly be influenced by the spending or saving of five shekalim. He is therefore not exempted from spending this amount on redemption.
The late Rav Moshe Feinstein offered another approach. When a man must spend money in order to buy the object required for a mitzvah, such as an esrog or a pair of Tefillin, he is exempt from doing so when the expenditure is greater than a fifth of his resources because he is then considered as helpless in acquiring the object. But when the mitzvah consists of spending money which he has, as in the case of redemption, no such exemption applies.
Return of the Redemption
Rabbi Tarfon and Rabbi Chanina were both kohanim who were in the custom of returning to the father, as a gift, the five shekalim they received from him for the redemption of a bechor.An interesting challenge is presented to this practice from an earlier ruling (Bechoros 26b) that one should not give the tithes due to a kohen to one who tries to drum up business by helping out in the grain warehouses. Such commercial behavior on the part of a kohen is described by the prophet Malachi as "corrupting the covenant of the Levite." How then did the two aforementioned sages make a practice of returning redemption money as a gift when this was tantamount to encouraging every prospective redeemer to favor them above all other kohanim?
The Rosh offers two resolutions of this problem. First of all, the redeemers had no guarantee that their money would be returned to them so that at the moment of redemption nothing had been done by the kohen to encourage favoring him above others. This, therefore, is not considered a corruption of the Levite covenant. Secondly, it is possible that these sages only returned the redemption money to redeemers who were truly needy so that no one was certain that he would qualify for such a gift.
