To most American Jews, even most Orthodox Jews, there is no question about the appropriateness of celebrating to Thanksgiving; to them, it is a secular holiday that represents values important in Judaism and in American culture. To many traditionalist Jews, however, commemorating any non-Jewish holiday raises questions about biblical and rabbinic law forbidding Jews to imitate non-Jewish customs and traditions.
Excerpted with permission from a longer version of this article, which can be found on the website Torah From Dixie.
Thanksgiving is a uniquely American holiday. It is no longer (and perhaps never was) a celebration affiliated with any particular religion or faith, although some in America celebrate with religious ceremonies….
The first and most significant issue in discussing whether it is halakhic [acceptable according to Jewish law] to celebrate Thanksgiving is whether it is permissible to eat a Thanksgiving meal, with the classical foods that American tradition indicates one should eat at this meal: turkey and cranberry sauce. Among the authorities of the previous generation, three different positions have been taken on this topic, and these three positions have each been accepted by various halakhic authorities of the current generation.
The Legal Background
However, before these three positions can be understood, a certain background into the nature of the prohibition against imitating Gentile customs must be understood. Tosafot [a medieval Talmud commentary] understands that two distinctly different types of customs are forbidden by the prohibition of imitating Gentile customs found in Leviticus 18:3. The first is idolatrous customs and the second is foolish customs found in the Gentile community, even if their origins are not idolatrous.
Rabbenu Nissim and Maharik disagree and rule that only customs that have a basis in idolatrous practices are prohibited. Apparently foolish–but secular–customs are permissible so long as they have a reasonable explanation (and are not immodest). Normative Halakhah follows the ruling of the Ran and Maharik.