DEUT683 Rabbi Meir, the Maharam of Rothenberg, Germany (thirteenth-century), taught that tithing is neither biblically or rabbinically required, but is rather a minhag, a custom (Responsa 131). This is the dominant view of Jewish legal scholars: a minimum of ten percent is the desirable amount to give, but there is no absolute biblical or rabbinic law requiring one to do so. However, the nineteenth-century legal scholar and author of Pitchei Teshuvah, Rabbi Avraham Tzvi Eisenstadt comments on the Maharam of Rothenberg's teaching that although the giving of ten percent is a custom, it has become a binding custom and "should not be annulled except in a case of great need" (Pitchei Teshuvah, Yoreh Deah 331:12). Other rabbis argue that tithing is not a custom but was instituted as obligatory by the Rabbis of the Talmud. [See, for example Rabbi Yechiel Michel Epstein: "In truth, these allocations of one-fifth and one-tenth are not Torah obligations, but the Rabbis [of the Talmud] associated them with the verse (Genesis 28:22), 'and of all that You give me, I will set aside a tithe for You'" (Arukh HaShulchan, Yoreh Deah 249:2. Another example: [this verse] rules, "You shall set aside every year a tenth part of all the yield of your sowing that is brought from the field"; In context, this does not seem to be an injunction to set aside a tithe for each year for the poor. Nonetheless, the medieval Tosafot commentary on the Talmud (see Ta'anit 9a) cites the Sifre, which derives from this verse the obligation to set aside a tenth of one's income for charitable purposes.] Finally, one of Judaism's greatest scholars, Rabbi Elijah of Vilna (eighteenth-century), the Vilna Gaon, insisted that the Torah obligates Jews to give a minimum of twenty, not ten, percent of their income to charity. In the Gaon's view, if one gives less, "then every minute of one's life one is transgressing several positive and negative commandments of the Torah, and one is considered as if one has rejected the whole of our holy Torah, heaven forbid." Fortunately for the souls of most modern Jews, the Gaon's is it decidedly minority view, and it is not clear which specific biblical commandments are being violated.