The passuk states “ובחקתיהם לא תלכו.” Onkelos translates “and do not follow their ideals and customs (ובנימוסי).” He translates the lashon חק as נימוסי, ideals and customs. The following passuk states “ואת חקתי תשמרו ללכת בהם” which Onkelos translates as “and My statutes (קימי) guard to follow them.” Here he translates חק differently, as קימי, My statutes. Similarly, in Parshas Kedoshim it states “ושמרתם את חקתי, and you shall guard My statutes” which Onkelos translates the lashon חק as קימי. And it states “ולא תלכו בחקת הגוי אשר אני משלח מפניכם, which Onkelos translates as “and do not follow in the ideals and customs of the nation that I am exiling from before you.” Here he translates the lashon חק as ideals and customs (בנמוסי).” Throughout these parshiyos Onkelos translates the lashon חק by Hashem’s commandments as “statute (קימי) whereas by the nations חק as ideals and customs. What is a חוק and what does נימוסי refer to?
Rashi explains a חוק as something which the king decreed that the yeitzer hara and the non-Jews question us, “why guard them?” It is a decree without a reason. The Ramban disagrees, there is a reason for all mitzvos, only we were not let known the entire reason for the statutes as their reason is infinite. נימוסי refers to things that are engraved (חקוקין) for them, a set practice, such as theaters or palaces of noblemen and circuses, places where oxen and other animals are enticed to ram into each other and battle.
In Parshas Vayikra it states “כל המנחה… לא תעשה חמץ כי כל שאר וכל דבש לא תקטירו ממנו אשה לה, any flour-offering… do not make chameitz, since from any yeast and any honey, do not offer it a korban to Hashem.” The Ramban brings b’shem the Moreh Nevuchim that the Rambam found in the non-Jew’s books that the custom for idolaters was to offer all of their meal-offerings of leaven and to mix honey in all of their korbanos. Therefore, Hashem assured for yeast or honey to be offered to Him. This is as Raboseinu explain about the מצבה, a one stone-altar. Originally, it was chosen by the Avos, and afterwards, Hashem hated it as it states “אשר שנא ה’ אלקיך, that which Hashem hated.” Although the Avos offered korbanos on it, Hashem hates it because idolaters made it a custom for idolatry. Since non-Jews have a custom to practice offering korbanos on it, Hashem hates it. The Steipler adds that whatever non-Jews do as a חק, a set permanent rule that they enact, even if it is not for their idolatry, we can’t do. The reason is that Hashem doesn’t want a Jew to practice the ideals and customs of the non-Jews which makes them similar to non-Jews.
The Nefesh HaGer is bothered, why does Onkelos change the translation of חק, from “statute by Hashem,” to “ideals by the nations?” He explains: Onkelos translates חק by Hashem’s statutes with the lashon קים since it reflects everlasting existence as there is the reward for mitzvos in the future world. This is as it states “וחי בהם,” which Onkelos translates “for everlasting life (לחיי עלמא),” which is in olam habah. Whereas by the nations, Onkelos translates חק with the lashon נימוס”” ideals and customs, since their statutes are based on time; when it is enacted, a group of people who contemplate and conclude to enact, and a specific place which is fitting for the enactment. When there is a decision to set up a rule, they enact it, and when they don’t want it, they cancel it. Since their rules are temporary, and not everlasting, Onkelos translates as נימוסי, ideals and customs.
May we fulfill Hashem’s mitzvos and merit everlasting reward.