By Rabbi Chaim Chazzan
May one request of a non-Jew to retrieve an object needed on Shabbos that was inadvertently left in a car before Shabbos?
The prohibition of amirah l’akum on Shabbos is comprised of three components: a) It is forbidden for a Jew to instruct a non-Jew to do an act that is prohibited for a Jew to do. b) When the non-Jew did an act for the Jew, even on his own volition, it is forbidden for the Jew to benefit from the act. c) The obligation to protest when there is concern that others might suspect that the non-Jew is doing the act on the behest of the Jew.
In general, one may do something on Shabbos even if there is a concern that a melachah might result, as long as one had no intention to achieve that result, provided that the result is not guaranteed to occur (this is known in halacha as a ‘davar shein miskaven’). For example: One may drag a light weighing bench on soil even though doing so may result in making a groove in the ground which is prohibited as a form of plowing, because the person dragging the bench has no intention of making the groove. But if the bench is heavy, and dragging it is bound to make a groove, it is prohibited (known in halacha as a psik reisha).
It is permissible to request a non-Jew to perform a psik reisha. For example: One who forgot to remove the light in one’s fridge before Shabbos may request of a non-Jew to open the fridge, although opening it will result in the light turning on, since that is not the non-Jew’s intention when opening the fridge.
Therefore, although a Jew may not open a car door on Shabbos, because opening the door turns on a light he may nevertheless request a non-Jew to retrieve for him as the melachah that occurs is unintentional (the fact that the car itself is muktzah is not a problemin this case).
 ראה בכ”ז בס’ אמירה לנכרי ע”פ שו”ע אדה”ז מאת הרשד”ב שי’ לוין, ס’ מלכים אומניך (זילברשטיין), ס’ אמירה לנכרי (דרברמדיקר) ועוד ספרים במקצוע זו
 שוע”ר סי’ רנג סעי’ י
 שו”ת אג”מ או”ח ח”ב סי’ סח ועוד פוסקים
 ילקוט יוסף סי’ שז סעי’ כה ובהערות
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